Virtualization is the creation of a virtual (rather than actual) version of something, such as an operating system, a server, a storage device or network resources.
You probably know a little about virtualization if you have ever divided your hard drive into different partitions. A partition is the logical division of a hard disk drive to create, in effect, two separate hard drives.
Operating system virtualization is the use of software to allow a piece of hardware to run multiple operating system images at the same time. The technology got its start on mainframes decades ago, allowing administrators to avoid wasting expensive processing power.
In 2005, virtualization software was adopted faster than anyone imagined, including the experts. There are three areas of IT where virtualization is making headroads, network virtualization, storage virtualization and server virtualization:
Network virtualization is a method of combining the available resources in a network by splitting up the available bandwidth into channels, each of which is independent from the others, and each of which can be assigned (or reassigned) to a particular server or device in real time. The idea is that virtualization disguises the true complexity of the network by separating it into manageable parts, much like your partitioned hard drive makes it easier to manage your files.
Storage virtualization is the pooling of physical storage from multiple network storage devices into what appears to be a single storage device that is managed from a central console. Storage virtualization is commonly used in storage area networks (SANs).
Server virtualization is the masking of server resources (including the number and identity of individual physical servers, processors, and operating systems) from server users. The intention is to spare the user from having to understand and manage complicated details of server resources while increasing resource sharing and utilization and maintaining the capacity to expand later.
Virtualization can be viewed as part of an overall trend in enterprise IT that includes autonomic computing, a scenario in which the IT environment will be able to manage itself based on perceived activity, and utility computing, in which computer processing power is seen as a utility that clients can pay for only as needed. The usual goal of virtualization is to centralize administrative tasks while improving scalability and work loads.
Sumber: www.whatis.com
Wednesday, December 3, 2008
Thursday, November 27, 2008
Web Server
A Web server is a program that, using the client/server model and the World Wide Web's Hypertext Transfer Protocol ( HTTP ), serves the files that form Web pages to Web users (whose computers contain HTTP clients that forward their requests). Every computer on the Internet that contains a Web site must have a Web server program. Two leading Web servers are Apache, the most widely-installed Web server, and Microsoft's Internet Information Server ( IIS ). Other Web servers include Novell's Web Server for users of its NetWare operating system and IBM's family of Lotus Domino servers, primarily for IBM's OS/390 and AS/400 customers.
Web servers often come as part of a larger package of Internet- and intranet-related programs for serving e-mail, downloading requests for File Transfer Protocol ( FTP ) files, and building and publishing Web pages. Considerations in choosing a Web server include how well it works with the operating system and other servers, its ability to handle server-side programming, security characteristics, and publishing, search engine, and site building tools that may come with it.
Web servers often come as part of a larger package of Internet- and intranet-related programs for serving e-mail, downloading requests for File Transfer Protocol ( FTP ) files, and building and publishing Web pages. Considerations in choosing a Web server include how well it works with the operating system and other servers, its ability to handle server-side programming, security characteristics, and publishing, search engine, and site building tools that may come with it.
Tuesday, November 25, 2008
Blade Server
Definition
A blade server is a server chassis housing multiple thin, modular electronic circuit boards, known as server blades. Each blade is a server in its own right, often dedicated to a single application. The blades are literally servers on a card, containing processors, memory, integrated network controllers, an optional fiber channel host bus adaptor (HBA) and other input/output (IO) ports.
Blade servers allow more processing power in less rack space, simplifying cabling and reducing power consumption. According to a SearchWinSystems.com article on server technology, enterprises moving to blade servers can experience as much as an 85% reduction in cabling for blade installations over conventional 1U or tower servers. With so much less cabling, IT administrators can spend less time managing the infrastructure and more time ensuring high availability.
Each blade typically comes with one or two local ATA or SCSI drives. For additional storage, blade servers can connect to a storage pool facilitated by a network-attached storage (NAS), Fiber Channel, or iSCSI storage-area network (SAN). The advantage of blade servers comes not only from the consolidation benefits of housing several servers in a single chassis, but also from the consolidation of associated resources (like storage and networking equipment) into a smaller architecture that can be managed through a single interface.
A blade server is sometimes referred to as a high-density server and is typically used in a clustering of servers that are dedicated to a single task, such as:
1. File sharing.
2. Web page serving and caching.
3. SSL encrypting of Web communication.
4. The transcoding of Web page content for smaller displays.
5. Streaming audio and video content.
Like most clustering applications, blade servers can also be managed to include load balancing and failover capabilities.
Sumber: www.whatis.com
A blade server is a server chassis housing multiple thin, modular electronic circuit boards, known as server blades. Each blade is a server in its own right, often dedicated to a single application. The blades are literally servers on a card, containing processors, memory, integrated network controllers, an optional fiber channel host bus adaptor (HBA) and other input/output (IO) ports.
Blade servers allow more processing power in less rack space, simplifying cabling and reducing power consumption. According to a SearchWinSystems.com article on server technology, enterprises moving to blade servers can experience as much as an 85% reduction in cabling for blade installations over conventional 1U or tower servers. With so much less cabling, IT administrators can spend less time managing the infrastructure and more time ensuring high availability.
Each blade typically comes with one or two local ATA or SCSI drives. For additional storage, blade servers can connect to a storage pool facilitated by a network-attached storage (NAS), Fiber Channel, or iSCSI storage-area network (SAN). The advantage of blade servers comes not only from the consolidation benefits of housing several servers in a single chassis, but also from the consolidation of associated resources (like storage and networking equipment) into a smaller architecture that can be managed through a single interface.
A blade server is sometimes referred to as a high-density server and is typically used in a clustering of servers that are dedicated to a single task, such as:
1. File sharing.
2. Web page serving and caching.
3. SSL encrypting of Web communication.
4. The transcoding of Web page content for smaller displays.
5. Streaming audio and video content.
Like most clustering applications, blade servers can also be managed to include load balancing and failover capabilities.
Sumber: www.whatis.com
Thursday, October 9, 2008
Cocaine Fact Sheet
What is Cocaine?
Cocaine originates from the coca plant and is a white powder that can be snorted or dissolved in water and injected. Crack cocaine is a smokable form, in various sized crystals, it is heated and the vapours smoked.
What are the Effects?
Cocaine is a strong stimulant that interferes with chemical messengers associated with pleasure and movement. A cocaine buzz gives you confidence and energy, though there is a chance of restlessness, irritability and aggression.
Cocaine has a tendency to decrease appetite and many users can become malnourished. Depression and paranoia are common side effects .
What are the Risks?
Persistent use of cocaine can effect mental health and withdrawal symptoms include anxiety and irritability. Crack cocaine can be more addictive with more extreme side effects. Snorting cocaine can lead to loss of sense of smell and permanent damage to the tissues in the nose.
Increased body temperature, heart rate and blood pressure are commonplace and prolonged use can cause heart problems and chest pains. It is possible to die from cocaine overdose, but most deaths are caused by heart failure or strokes.
Cocaine use during pregnancy can lead to birth defects and low birthweight babies. There is also a chance that the baby may be born addicted to the drug.
The Law
Cocaine is a Class A drug. It is illegal to produce, supply or possess it. The maximum penalty for possession of drugs is seven years in prison or a fine. For supply: a maximum sentence of life imprisonment and a fine.
Cocaine originates from the coca plant and is a white powder that can be snorted or dissolved in water and injected. Crack cocaine is a smokable form, in various sized crystals, it is heated and the vapours smoked.
What are the Effects?
Cocaine is a strong stimulant that interferes with chemical messengers associated with pleasure and movement. A cocaine buzz gives you confidence and energy, though there is a chance of restlessness, irritability and aggression.
Cocaine has a tendency to decrease appetite and many users can become malnourished. Depression and paranoia are common side effects .
What are the Risks?
Persistent use of cocaine can effect mental health and withdrawal symptoms include anxiety and irritability. Crack cocaine can be more addictive with more extreme side effects. Snorting cocaine can lead to loss of sense of smell and permanent damage to the tissues in the nose.
Increased body temperature, heart rate and blood pressure are commonplace and prolonged use can cause heart problems and chest pains. It is possible to die from cocaine overdose, but most deaths are caused by heart failure or strokes.
Cocaine use during pregnancy can lead to birth defects and low birthweight babies. There is also a chance that the baby may be born addicted to the drug.
The Law
Cocaine is a Class A drug. It is illegal to produce, supply or possess it. The maximum penalty for possession of drugs is seven years in prison or a fine. For supply: a maximum sentence of life imprisonment and a fine.
Monday, September 22, 2008
Mengoptimalkan Windows Vista
Windows Vista datang dengan segudang fitur. Beberapa fitur membuat tampilan Vista sangat menarik, beberapa fitur bisa membantu orang kantoran, beberapa fitur harus berjalan agar Vista berfungsi.
Sayang, sekian dari beberapa fitur itu bisa membikin kerja komputer menurun. Fitur yang mempercantik tampilan Vista ternyata menjadi beban bagi kerja kartu grafis. Fitur buat orang kantoran yang tidak dipakai orang rumahan membebani memori. Fitur-fitur yang kurang terpakai itu baiknya dimatikan saja agar kerja komputer lebih cepat.
Tepatnya, fitur apa saja yang harus dimatikan? Apa semua fitur yang PCplus beritahu di artikel ini? Tidak ada jawaban yang pasti, tergantung pada bagaimana komputer digunakan dan selera sang empunya komputer. Pada laptop milik PCplus, hanya sebagian fitur yang dimatikan.
Sebelum mengutak-atik fitur Vista, sebaiknya bikin dulu “restore point”. Jadi, kalau ada apa-apa setelah sebuah fitur dimatikan, tinggal kembali lagi ke “restore point” itu.
Sidebar
Sidebar berisi aplikasi-aplikasi kecil, seperti jam, slide show foto, serta RSS. Pengguna PC harus membayar dengan menurunnya kerja komputer untuk hal-hal kecil itu. Kalau dimatikan, kerja PC bisa lebih cepat. Cepatnya itu terasa saat Windows dinyalakan (boot).
Cara mematikannya seperti ini.
1. Klik kanan di Sidebar (di area mana pun), lalu klik [Close Sidebar].
2. Hilangkan tanda centang pada [Uncheck Start Sidebar when Windows starts].
3. Klik [OK].
Aero
Vista punya Aero yang merupakan suatu paket yang mempercantik tampilan Vista. Kalau diaktifkan, Vista akan punya berbagai efek yang harus diakui memang cukup mengagumkan.
Salah satu efek yang dibanggakan Microsoft adalah Flip 3D. Fungsinya untuk berpindah aplikasi, tetapi dengan efek 3D. Flip 3D mempercantik fungsi pindah aplikasi yang diakses dengan tombol [Alt] + [Tab]. Flip 3D sendiri diakses dengan tombol [Windows] + [Tab].
Sayangnya, pada komputer yang spesifikasi perangkat kerasnya pas-pasan, Aero menjadi beban. Begitu juga pada komputer yang isinya sudah kelewat banyak.
Berikut cara mematikan Aero.
1. Klik kanan pada desktop, lalu klik [Personalize].
2. Klik [Windows Color and Appearance].
3. Pada kotak yang muncul, klik [Open classic appearances properties for more color options]. Enggak menemukan opsi itu? Berarti, Aero memang sudah tidak aktif. Ketika spesifikasi perangkat keras tidak memenuhi syarat, Aero memang otomatis mati.
4. Pilih [Windows Vista Basic].
5. Klik [OK].
Tidak semua efek yang cantik berasal dari Aero. Ada beberapa efek yang memang sudah ada di Windows, misalnya efek bergeser dari jendela yang di-minimize atau efek munculnya petunjuk (tooltip).
Efek-efek itu bisa juga dimatikan. Caranya begini.
1. Klik [Start], klik kanan pada [Computer] lalu klik [Properties].
2. Klik [Advanced System Properties].
3. Pada kotak yang muncul, klik tab [Advanced].
4. Klik [Settings] yang ada di kotak “Performance”.
5. Lihatlah pilihan-pilihan efek yang muncul. Gampangnya, matikan saja semua. Tapi, bisa saja sebagian yang dimatikan. Hilangkan tanda centang pada efek yang hendak dimatikan.
Internet Printing Client
Ada loh layanan cetak online. Orang bisa mengirim foto ke penyedia layanan, foto dicetak, lalu dikirim ke suatu alamat. Kalau layanan seperti ini tidak pernah digunakan, matikan saja fitur “Internet Printing Client”.
Caranya:
1. Buka Control Panel, lalu klik [Programs and Features].
2. Klik [Turn Windows features on or off] yang ada di sebelah kiri.
3. Di kotak “Windows Features”, klik [Print Services].
4. Hilangkan tanda centang pada [Internet Printing Client].
5. Klik [OK].
6. Restart komputer setelah diminta.
Windows Meeting Space
Meeting Space adalah sebuah fitur yang memungkinkan seorang pengguna komputer berbagi file dengan kawannya yang berada dalam 1 jaringan komputer. File itu bukan cuma dibagi, tapi bisa diedit berbarengan. Kalau fitur ini tidak pernah dipakai, dimatikan saja.
Ini caranya:
1. Buka Control Panel, lalu klik [Programs and Features].
2. Klik [Turn Windows features on or off] yang ada di sebelah kiri.
3. Hilangkan tanda centang pada “Windows Meeting Space”.
4. Klik [OK].
Fitur-Fitur Tablet PC
Vista dilengkapi dengan fitur untuk Tablet PC. Kalau saja Vista tidak di-install di Tablet PC, buat apa fiturnya diaktifkan. Toh, tidak akan digunakan.
Cara mematikannya:
1. Buka Control Panel, lalu klik [Programs and Features].
2. Klik [Turn Windows features on or off] yang ada di sebelah kiri.
3. Di kotak “Windows Features”, hilangkan tanda centang pada [Tablet PC Optional Components].
4. Klik [Start], ketikan “services” di kotak pencarian. Ketika muncul [Services] di hasil pencarian, klik di situ.
5. Cari [Tablet PC Input Services]. Kalau sudah ketemu, klik ganda di situ.
6. Pada menu drop-down “Startup type”, pilih [Disabled].
7. Klik [OK].
ReadyBoost
ReadyBoost sedianya mempercepat Vista. Tapi, apa peningkatan kecepatannya sangat terasa? Pada beberapa kasus, penggunaan ReadyBoost justru memperlambat komputer.
ReadyBoost bisa dimatikan di bagian Services dengan cara:
1. Klik [Start], ketikan “services” di kotak pencarian. Klik [Services] pada hasil pencarian.
2. Klik ganda pada [ReadyBoost].
3. Pada menu drop-down “Startup type”, pilih [Disabled].
4. Klik [OK].
Laporan Kesalahan
Kalau suatu program mendadak berhenti bekerja—entah program punya Windows, entah program lain—Vista akan menawarkan apakah pengguna ingin melaporkan kesalahan itu ke Microsoft. Idealnya, Microsoft akan mencari tahu apa yang menyebabkan kesalahan itu. Yah, kalau PCplus sih jarang mengirimkan laporan. Jadi, fitur laporan kesalahan itu PCplus matikan.
Begini cara mematikannya.
1. Klik [Start], ketikan “services” di kotak pencarian. Klik [Services] pada hasil pencarian.
2. Klik ganda pada [Windows Error Reporting Service].
3. Pada menu drop-down “Startup type”, pilih [Disabled].
4. Klik [OK].
Indeks Pencarian
PCplus perlu berpikir berulang kali untuk mematikan fitur ini. Soalnya, fitur ini sangat berguna untuk mencari file, program, atau e-mail dengan cepat. Kalau fitur ini dimatikan, pencarian file dan lain-lain yang seharusnya ketemu dalam hitungan detik, bisa baru ketemu setelah beberapa menit pencarian.Tapi, kalau fitur ini dihidupkan, Vista akan terus menerus membuat indeks selama isi harddisk berubah. Beberapa orang yang spesifikasi komputernya pas-pasan, bolehlah mematikan fitur ini.
Cara mematikannya:
1. Klik [Start], ketikan “services” di kotak pencarian. Klik [Services] pada hasil pencarian.
2. Klik ganda pada [Windows Search].
3. Pilih [Disabled] pada menu drop-down [Startup type].
4. Klik [OK].
Sumber: PC Plus
Sayang, sekian dari beberapa fitur itu bisa membikin kerja komputer menurun. Fitur yang mempercantik tampilan Vista ternyata menjadi beban bagi kerja kartu grafis. Fitur buat orang kantoran yang tidak dipakai orang rumahan membebani memori. Fitur-fitur yang kurang terpakai itu baiknya dimatikan saja agar kerja komputer lebih cepat.
Tepatnya, fitur apa saja yang harus dimatikan? Apa semua fitur yang PCplus beritahu di artikel ini? Tidak ada jawaban yang pasti, tergantung pada bagaimana komputer digunakan dan selera sang empunya komputer. Pada laptop milik PCplus, hanya sebagian fitur yang dimatikan.
Sebelum mengutak-atik fitur Vista, sebaiknya bikin dulu “restore point”. Jadi, kalau ada apa-apa setelah sebuah fitur dimatikan, tinggal kembali lagi ke “restore point” itu.
Sidebar
Sidebar berisi aplikasi-aplikasi kecil, seperti jam, slide show foto, serta RSS. Pengguna PC harus membayar dengan menurunnya kerja komputer untuk hal-hal kecil itu. Kalau dimatikan, kerja PC bisa lebih cepat. Cepatnya itu terasa saat Windows dinyalakan (boot).
Cara mematikannya seperti ini.
1. Klik kanan di Sidebar (di area mana pun), lalu klik [Close Sidebar].
2. Hilangkan tanda centang pada [Uncheck Start Sidebar when Windows starts].
3. Klik [OK].
Aero
Vista punya Aero yang merupakan suatu paket yang mempercantik tampilan Vista. Kalau diaktifkan, Vista akan punya berbagai efek yang harus diakui memang cukup mengagumkan.
Salah satu efek yang dibanggakan Microsoft adalah Flip 3D. Fungsinya untuk berpindah aplikasi, tetapi dengan efek 3D. Flip 3D mempercantik fungsi pindah aplikasi yang diakses dengan tombol [Alt] + [Tab]. Flip 3D sendiri diakses dengan tombol [Windows] + [Tab].
Sayangnya, pada komputer yang spesifikasi perangkat kerasnya pas-pasan, Aero menjadi beban. Begitu juga pada komputer yang isinya sudah kelewat banyak.
Berikut cara mematikan Aero.
1. Klik kanan pada desktop, lalu klik [Personalize].
2. Klik [Windows Color and Appearance].
3. Pada kotak yang muncul, klik [Open classic appearances properties for more color options]. Enggak menemukan opsi itu? Berarti, Aero memang sudah tidak aktif. Ketika spesifikasi perangkat keras tidak memenuhi syarat, Aero memang otomatis mati.
4. Pilih [Windows Vista Basic].
5. Klik [OK].
Tidak semua efek yang cantik berasal dari Aero. Ada beberapa efek yang memang sudah ada di Windows, misalnya efek bergeser dari jendela yang di-minimize atau efek munculnya petunjuk (tooltip).
Efek-efek itu bisa juga dimatikan. Caranya begini.
1. Klik [Start], klik kanan pada [Computer] lalu klik [Properties].
2. Klik [Advanced System Properties].
3. Pada kotak yang muncul, klik tab [Advanced].
4. Klik [Settings] yang ada di kotak “Performance”.
5. Lihatlah pilihan-pilihan efek yang muncul. Gampangnya, matikan saja semua. Tapi, bisa saja sebagian yang dimatikan. Hilangkan tanda centang pada efek yang hendak dimatikan.
Internet Printing Client
Ada loh layanan cetak online. Orang bisa mengirim foto ke penyedia layanan, foto dicetak, lalu dikirim ke suatu alamat. Kalau layanan seperti ini tidak pernah digunakan, matikan saja fitur “Internet Printing Client”.
Caranya:
1. Buka Control Panel, lalu klik [Programs and Features].
2. Klik [Turn Windows features on or off] yang ada di sebelah kiri.
3. Di kotak “Windows Features”, klik [Print Services].
4. Hilangkan tanda centang pada [Internet Printing Client].
5. Klik [OK].
6. Restart komputer setelah diminta.
Windows Meeting Space
Meeting Space adalah sebuah fitur yang memungkinkan seorang pengguna komputer berbagi file dengan kawannya yang berada dalam 1 jaringan komputer. File itu bukan cuma dibagi, tapi bisa diedit berbarengan. Kalau fitur ini tidak pernah dipakai, dimatikan saja.
Ini caranya:
1. Buka Control Panel, lalu klik [Programs and Features].
2. Klik [Turn Windows features on or off] yang ada di sebelah kiri.
3. Hilangkan tanda centang pada “Windows Meeting Space”.
4. Klik [OK].
Fitur-Fitur Tablet PC
Vista dilengkapi dengan fitur untuk Tablet PC. Kalau saja Vista tidak di-install di Tablet PC, buat apa fiturnya diaktifkan. Toh, tidak akan digunakan.
Cara mematikannya:
1. Buka Control Panel, lalu klik [Programs and Features].
2. Klik [Turn Windows features on or off] yang ada di sebelah kiri.
3. Di kotak “Windows Features”, hilangkan tanda centang pada [Tablet PC Optional Components].
4. Klik [Start], ketikan “services” di kotak pencarian. Ketika muncul [Services] di hasil pencarian, klik di situ.
5. Cari [Tablet PC Input Services]. Kalau sudah ketemu, klik ganda di situ.
6. Pada menu drop-down “Startup type”, pilih [Disabled].
7. Klik [OK].
ReadyBoost
ReadyBoost sedianya mempercepat Vista. Tapi, apa peningkatan kecepatannya sangat terasa? Pada beberapa kasus, penggunaan ReadyBoost justru memperlambat komputer.
ReadyBoost bisa dimatikan di bagian Services dengan cara:
1. Klik [Start], ketikan “services” di kotak pencarian. Klik [Services] pada hasil pencarian.
2. Klik ganda pada [ReadyBoost].
3. Pada menu drop-down “Startup type”, pilih [Disabled].
4. Klik [OK].
Laporan Kesalahan
Kalau suatu program mendadak berhenti bekerja—entah program punya Windows, entah program lain—Vista akan menawarkan apakah pengguna ingin melaporkan kesalahan itu ke Microsoft. Idealnya, Microsoft akan mencari tahu apa yang menyebabkan kesalahan itu. Yah, kalau PCplus sih jarang mengirimkan laporan. Jadi, fitur laporan kesalahan itu PCplus matikan.
Begini cara mematikannya.
1. Klik [Start], ketikan “services” di kotak pencarian. Klik [Services] pada hasil pencarian.
2. Klik ganda pada [Windows Error Reporting Service].
3. Pada menu drop-down “Startup type”, pilih [Disabled].
4. Klik [OK].
Indeks Pencarian
PCplus perlu berpikir berulang kali untuk mematikan fitur ini. Soalnya, fitur ini sangat berguna untuk mencari file, program, atau e-mail dengan cepat. Kalau fitur ini dimatikan, pencarian file dan lain-lain yang seharusnya ketemu dalam hitungan detik, bisa baru ketemu setelah beberapa menit pencarian.Tapi, kalau fitur ini dihidupkan, Vista akan terus menerus membuat indeks selama isi harddisk berubah. Beberapa orang yang spesifikasi komputernya pas-pasan, bolehlah mematikan fitur ini.
Cara mematikannya:
1. Klik [Start], ketikan “services” di kotak pencarian. Klik [Services] pada hasil pencarian.
2. Klik ganda pada [Windows Search].
3. Pilih [Disabled] pada menu drop-down [Startup type].
4. Klik [OK].
Sumber: PC Plus
Sunday, September 21, 2008
IT Security Attackers
Virus
Virus merupakan software yang dapat menggandakan sistem komputer dan berpotensi menempelkan diri dengan setiap aplikasi software. Ia menyerang mulai dari boot sector, terminate and stay resident (TSR), sampai software aplikasi. Virus bisa menyebabkan data tercuri/hilang, mutasi mesin, hingga kerusakan jaringan. Virus bisa dideteksi dengan melihat gejala seperti, perubahan ukuran dan keterangan waktu/tanggal file, komputer lambat saat dihidupkan maupun bekerja, kegagalan system secara tiba-tiba maupun frekuentatif, perubahan system waktu dan tanggal, memori computer rendah atau timbul bad blocks pada disk.
Cara mengantisipasinya adalah dengan membatasi konektivitas dan download, menggunakan media resmi saja untuk memasukkan data atau software, mengatur kontrol akses dengan tegas. Virus biasanya tidak dapat beraksi jika host application (sumber aplikasi utamanya, mis. CD program) dijalankan.
Sementara cara menanggulanginya adalah memantau, mengidentifikasi, dan memulihkan dengan menggunkan antivirus scanners ( mencari virus-virus yang dikenali) ataupun antivirus monitors (mencari perilaku virus yang terkait dengan aplikasi), serta berusaha memperbaiki sumber infeksi.
Worms
Worm adalah program yang berjalan mandiri dan berpindah-pindah dari satu komputer ke komputer lain melalui jaringan yang terhubung. Worm memperbanyak diri dengan cepat dan membuat penuh jaringan sehingga menimbulkan kegagalan dan kerugian dalam pelayanan. Worm juga bisa mengandung virus yang dapat menginfeksi file komputer. Pendeteksian dan penanggulangan worm serupa dengan virus. Hanya saja, worm lebih bandel dibandingkan virus. Worm masih bisa beraksi ketika host application dijalankan. Untuk mengantisipasi worm bisa dengan membatasi konektivitas dan memberlakukan firewalls.
Denial Of Service (DoS)
DoS menyerang kelangsungan kegiatan jasa di internet. Hal ini marak terjadi karena website adalah pintu yang terbuka dengan kemungkinan penyalahgunaan. Seseorang atau sekelompok orang dengan mudah bisa memenuhi web server dengan lalu lintas tak berguna. Tujuannya membuat situs tersebut tampak sibuk sehingga pengguna yang sesungguhnya memerlukan situs itu tidak bisa masuk.
Trojan Horse
Salah satu worm yang terkenal adalah Trojan Horse. Kedok Trojan Horse bermacam-macam. Ia bisa berpura-pura sebagai program yang berguna. Ia pun bisa menjadi virus yang secara sengaja disematkan pada program utama yang berguna untuk disebarluaskan.
Tak seperti worm yang bisa menggandakan diri sendiri, Trojan Horse membutuhkan kerjasama pengguna (user) karena memungkinnya menerabas kontrol otomatis. Oleh karena itu, cara terbaik untuk mengantisipasi Trojan Horse adalah SDM/user yang terlatih.
Antisipasi dan pendeteksian Trojan Horse sama halnya dengan virus dan worm. Sedangkan untuk menanggulanginya, perlu dicatat bahwa kesiapsiagaan bukan semata-mata tanggung jawab system admin, melainkan juga semua pengguna jaringan (all network users).
Password Cracking Software
Password Cracking Software adalah software yang memecahkan enkripsi yang tersimpan dalam server. Ia bekerja dengan baik pada passwords sederhana dan membuat para penyerang untuk mengumpulkan akses melalui akun pengguna yang sah. Hal ini mungkin terjadi karena beberapa users memilih password yang mudah dipecahkan.
Snooping
Snooping adalah suatu pemantauan elektronik terhadap jaringan digital untuk mengetahui password atau data lainnya. Ada beragam teknik snooping atau juga dikenal sebagai eavesdropping, yakni: shoulder surfing (pengamatan langsung terhadap display monitor seseorang untuk memperoleh akses), dumpster diving (mengakses untuk memperoleh password dan data lainnya), digital sniffing (pengamatan elektronik terhadap jaringan untuk mengungkap password atau data lainnya). Penanggulangannya adalah dengan mengubah skema sandi atau menggunakan perangkat monitoring network untuk mengembalikan ke petunjuk semula.
Masquerade
Masquerade adalah suatu tindakan mengakses sistem komputer orang lain dengan berpura-pura memiliki identitas pengguna resmi komputer tersebut. Pencegahannya bisa dilakukan dengan membatasi akses user kepada jaringan maupun fungsi perintah administrator dan menerapkan level bertingkat pada administrator dengan masing-masing tingkat memiliki perbedaan ketentuan. Perlawanan terhadap masquerade dilakukan dengan mengubah password user atau menggunakan fungsi administrator standar untuk membatasi titik akses, kemudian melacak kembali ke petunjuk semula.
Virus merupakan software yang dapat menggandakan sistem komputer dan berpotensi menempelkan diri dengan setiap aplikasi software. Ia menyerang mulai dari boot sector, terminate and stay resident (TSR), sampai software aplikasi. Virus bisa menyebabkan data tercuri/hilang, mutasi mesin, hingga kerusakan jaringan. Virus bisa dideteksi dengan melihat gejala seperti, perubahan ukuran dan keterangan waktu/tanggal file, komputer lambat saat dihidupkan maupun bekerja, kegagalan system secara tiba-tiba maupun frekuentatif, perubahan system waktu dan tanggal, memori computer rendah atau timbul bad blocks pada disk.
Cara mengantisipasinya adalah dengan membatasi konektivitas dan download, menggunakan media resmi saja untuk memasukkan data atau software, mengatur kontrol akses dengan tegas. Virus biasanya tidak dapat beraksi jika host application (sumber aplikasi utamanya, mis. CD program) dijalankan.
Sementara cara menanggulanginya adalah memantau, mengidentifikasi, dan memulihkan dengan menggunkan antivirus scanners ( mencari virus-virus yang dikenali) ataupun antivirus monitors (mencari perilaku virus yang terkait dengan aplikasi), serta berusaha memperbaiki sumber infeksi.
Worms
Worm adalah program yang berjalan mandiri dan berpindah-pindah dari satu komputer ke komputer lain melalui jaringan yang terhubung. Worm memperbanyak diri dengan cepat dan membuat penuh jaringan sehingga menimbulkan kegagalan dan kerugian dalam pelayanan. Worm juga bisa mengandung virus yang dapat menginfeksi file komputer. Pendeteksian dan penanggulangan worm serupa dengan virus. Hanya saja, worm lebih bandel dibandingkan virus. Worm masih bisa beraksi ketika host application dijalankan. Untuk mengantisipasi worm bisa dengan membatasi konektivitas dan memberlakukan firewalls.
Denial Of Service (DoS)
DoS menyerang kelangsungan kegiatan jasa di internet. Hal ini marak terjadi karena website adalah pintu yang terbuka dengan kemungkinan penyalahgunaan. Seseorang atau sekelompok orang dengan mudah bisa memenuhi web server dengan lalu lintas tak berguna. Tujuannya membuat situs tersebut tampak sibuk sehingga pengguna yang sesungguhnya memerlukan situs itu tidak bisa masuk.
Trojan Horse
Salah satu worm yang terkenal adalah Trojan Horse. Kedok Trojan Horse bermacam-macam. Ia bisa berpura-pura sebagai program yang berguna. Ia pun bisa menjadi virus yang secara sengaja disematkan pada program utama yang berguna untuk disebarluaskan.
Tak seperti worm yang bisa menggandakan diri sendiri, Trojan Horse membutuhkan kerjasama pengguna (user) karena memungkinnya menerabas kontrol otomatis. Oleh karena itu, cara terbaik untuk mengantisipasi Trojan Horse adalah SDM/user yang terlatih.
Antisipasi dan pendeteksian Trojan Horse sama halnya dengan virus dan worm. Sedangkan untuk menanggulanginya, perlu dicatat bahwa kesiapsiagaan bukan semata-mata tanggung jawab system admin, melainkan juga semua pengguna jaringan (all network users).
Password Cracking Software
Password Cracking Software adalah software yang memecahkan enkripsi yang tersimpan dalam server. Ia bekerja dengan baik pada passwords sederhana dan membuat para penyerang untuk mengumpulkan akses melalui akun pengguna yang sah. Hal ini mungkin terjadi karena beberapa users memilih password yang mudah dipecahkan.
Snooping
Snooping adalah suatu pemantauan elektronik terhadap jaringan digital untuk mengetahui password atau data lainnya. Ada beragam teknik snooping atau juga dikenal sebagai eavesdropping, yakni: shoulder surfing (pengamatan langsung terhadap display monitor seseorang untuk memperoleh akses), dumpster diving (mengakses untuk memperoleh password dan data lainnya), digital sniffing (pengamatan elektronik terhadap jaringan untuk mengungkap password atau data lainnya). Penanggulangannya adalah dengan mengubah skema sandi atau menggunakan perangkat monitoring network untuk mengembalikan ke petunjuk semula.
Masquerade
Masquerade adalah suatu tindakan mengakses sistem komputer orang lain dengan berpura-pura memiliki identitas pengguna resmi komputer tersebut. Pencegahannya bisa dilakukan dengan membatasi akses user kepada jaringan maupun fungsi perintah administrator dan menerapkan level bertingkat pada administrator dengan masing-masing tingkat memiliki perbedaan ketentuan. Perlawanan terhadap masquerade dilakukan dengan mengubah password user atau menggunakan fungsi administrator standar untuk membatasi titik akses, kemudian melacak kembali ke petunjuk semula.
Friday, August 8, 2008
Di Inggris, Ponsel Curian Tak Lagi Berharga
Pemakai ponsel di Inggris dimanjakan sebuah fasilitas anti pencurian. Setiap ponsel yang dicuri di sana tidak akan bisa digunakan lagi sehingga tak ada harganya. Maling pun kini dipastikan segan mencuri ponsel, betapapun mahal harganya.
Pasalnya, ponsel yang dicuri akan dikunci operatornya dalam waktu selambatnya 48 jam. Sesudahnya melalui koordinasi tertentu, seluruh operator yang ada di Inggris Raya akan mengunci ponsel itu sehingga sama sekali tak bisa digunakan di tanah Britania meski sang pencuri berpindah jaringan ponsel.
Sistem penguncian ini diujicoba oleh lembaga MICAF (Mobile Industry Crime Action Forum) selama bulan September. Namun demikian, masalah yang sekarang mengemuka adalah menyosialisasikan inisiatif ini agar para maling tahu mencuri ponsel di Inggris sekarang adalah perbuatan sia-sia. Tahun lalu saja menurut data pemerintah, sebanyak 800.000 ponsel dicuri di Inggris.
Ponsel yang dicuri diblok oleh jaringan dengan memanfaatkan IMEI (International Mobile Equipment Identity) ponsel itu, yaitu nomor unik sebagai pengidentifikasi tiap ponsel. Berkaitan dengan hal ini, sejak April di Inggris, mengubah IMEI handset dianggap sebagai sebuah kejahatan. Namun demikian, dianggap lebih efektif jika produsen ponsel mampu mempersulit proses pengubahan IMEI ini.
Seperti dikutip detikINET dari TheRegister, Senin (29/10/2007), semakin banyak operator jaringan GSM di dunia yang mau memblok ponsel yang tercuri. Agar lebih efektif untuk menurunkan tingkat pencurian, disebutkan perlunya kampanye intensif bahwa mencuri ponsel adalah perbuatan sia-sia.
Sumber: www.detikinet.com (29/10/2007)
Pasalnya, ponsel yang dicuri akan dikunci operatornya dalam waktu selambatnya 48 jam. Sesudahnya melalui koordinasi tertentu, seluruh operator yang ada di Inggris Raya akan mengunci ponsel itu sehingga sama sekali tak bisa digunakan di tanah Britania meski sang pencuri berpindah jaringan ponsel.
Sistem penguncian ini diujicoba oleh lembaga MICAF (Mobile Industry Crime Action Forum) selama bulan September. Namun demikian, masalah yang sekarang mengemuka adalah menyosialisasikan inisiatif ini agar para maling tahu mencuri ponsel di Inggris sekarang adalah perbuatan sia-sia. Tahun lalu saja menurut data pemerintah, sebanyak 800.000 ponsel dicuri di Inggris.
Ponsel yang dicuri diblok oleh jaringan dengan memanfaatkan IMEI (International Mobile Equipment Identity) ponsel itu, yaitu nomor unik sebagai pengidentifikasi tiap ponsel. Berkaitan dengan hal ini, sejak April di Inggris, mengubah IMEI handset dianggap sebagai sebuah kejahatan. Namun demikian, dianggap lebih efektif jika produsen ponsel mampu mempersulit proses pengubahan IMEI ini.
Seperti dikutip detikINET dari TheRegister, Senin (29/10/2007), semakin banyak operator jaringan GSM di dunia yang mau memblok ponsel yang tercuri. Agar lebih efektif untuk menurunkan tingkat pencurian, disebutkan perlunya kampanye intensif bahwa mencuri ponsel adalah perbuatan sia-sia.
Sumber: www.detikinet.com (29/10/2007)
Tuesday, April 29, 2008
Network Administration Tools commands
netconf (as root)
A very good menu-driven setup of your network.
ping machine_name
Check if you can contact another machine (give the machine's name or IP), press [Ctrl]C when done (it keeps going).
route -n
Show the kernel routing table.
nslookup host_to_find
Query your default domain name server (DNS) for an Internet name (or IP number) host_to_find. This way you can check if your DNS works. You can also find out the name of the host of which you only know the IP number.
traceroute host_to_trace
Have a look how you messages trave to host_to_trace (which is either a host name or IP number).
ipfwadm -F -p m (for RH5.2, seen next command for RH6.0)
Set up the firewall IP forwarding policy to masquerading. (Not very secure but simple.) Purpose: all computers from your home network will appear to the outside world as one very busy machine and, for example, you will be allowed to browse the Internet from all computers at once.
echo 1 > /proc/sys/net/ipv4/ip_forward
ipfwadm-wrapper -F -p deny
ipfwadm-wrapper -F -a m -S xxx.xxx.xxx.0/24 -D 0.0.0.0/0
(three commands, RH6.0).
Does the same as the previous command. Substitute the "x"s with digits of your class "C" IP address that you assigned to your home network. See here for more details. In RH6.1, masquarading seems broken to me--I think I will install Mandrake Linux:).
ifconfig (as root)
Display info on the network interfaces currently active (ethernet, ppp, etc). Your first ethernet should show up as eth0, second as eth1, etc, first ppp over modem as ppp0, second as ppp1, etc. The "lo" is the "loopback only" interface which should be always active. Use the options (see ifconfig --help) to configure the interfaces.
ifup interface_name (/sbin/ifup to it run as a user)
Startup a network interface. E.g.: ifup eth0 ifup ppp0 Users can start up or shutdown the ppp interface only when the right permission was checked during the ppp setup (using netconf ). To start a ppp interface (dial-up connection), I normally use kppp available under kde menu "internet".
ifdown interface_name (/sbin/ifdown to run it as a user).
Shut down the network interface. E.g.: ifdown ppp0 Also, see the previous command.
netstat more
Displays a lot (too much?) information on the status of your network.
A very good menu-driven setup of your network.
ping machine_name
Check if you can contact another machine (give the machine's name or IP), press [Ctrl]C when done (it keeps going).
route -n
Show the kernel routing table.
nslookup host_to_find
Query your default domain name server (DNS) for an Internet name (or IP number) host_to_find. This way you can check if your DNS works. You can also find out the name of the host of which you only know the IP number.
traceroute host_to_trace
Have a look how you messages trave to host_to_trace (which is either a host name or IP number).
ipfwadm -F -p m (for RH5.2, seen next command for RH6.0)
Set up the firewall IP forwarding policy to masquerading. (Not very secure but simple.) Purpose: all computers from your home network will appear to the outside world as one very busy machine and, for example, you will be allowed to browse the Internet from all computers at once.
echo 1 > /proc/sys/net/ipv4/ip_forward
ipfwadm-wrapper -F -p deny
ipfwadm-wrapper -F -a m -S xxx.xxx.xxx.0/24 -D 0.0.0.0/0
(three commands, RH6.0).
Does the same as the previous command. Substitute the "x"s with digits of your class "C" IP address that you assigned to your home network. See here for more details. In RH6.1, masquarading seems broken to me--I think I will install Mandrake Linux:).
ifconfig (as root)
Display info on the network interfaces currently active (ethernet, ppp, etc). Your first ethernet should show up as eth0, second as eth1, etc, first ppp over modem as ppp0, second as ppp1, etc. The "lo" is the "loopback only" interface which should be always active. Use the options (see ifconfig --help) to configure the interfaces.
ifup interface_name (/sbin/ifup to it run as a user)
Startup a network interface. E.g.: ifup eth0 ifup ppp0 Users can start up or shutdown the ppp interface only when the right permission was checked during the ppp setup (using netconf ). To start a ppp interface (dial-up connection), I normally use kppp available under kde menu "internet".
ifdown interface_name (/sbin/ifdown to run it as a user).
Shut down the network interface. E.g.: ifdown ppp0 Also, see the previous command.
netstat more
Displays a lot (too much?) information on the status of your network.
Monday, April 28, 2008
Accessing Drive Partition commands
mount
See here for details on mounting drives. Examples are shown in the next commands.
mount -t auto /dev/fd0 /mnt/floppy (as root)
Mount the floppy. The directory /mnt/floppy must exist, be empty and NOT be your current directory.
mount -t auto /dev/cdrom /mnt/cdrom (as root)
Mount the CD. You may need to create/modify the /dev/cdrom file depending where your CDROM is. The directory /mnt/cdrom must exist, be empty and NOT be your current directory.
mount /mnt/floppy (as user or root)
Mount a floppy as user. The file /etc/fstab must be set up to do this. The directory /mnt/floppy must not be your current directory.
mount /mnt/cdrom (as user or root)
Mount a CD as user. The file /etc/fstab must be set up to do this. The directory /mnt/cdrom must not be your current directory.
umount /mnt/floppy
Unmount the floppy. The directory /mnt/floppy must not be your (or anybody else's) current working directory. Depending on your setup, you might not be able to unmount a drive that you didn't mount.
See here for details on mounting drives. Examples are shown in the next commands.
mount -t auto /dev/fd0 /mnt/floppy (as root)
Mount the floppy. The directory /mnt/floppy must exist, be empty and NOT be your current directory.
mount -t auto /dev/cdrom /mnt/cdrom (as root)
Mount the CD. You may need to create/modify the /dev/cdrom file depending where your CDROM is. The directory /mnt/cdrom must exist, be empty and NOT be your current directory.
mount /mnt/floppy (as user or root)
Mount a floppy as user. The file /etc/fstab must be set up to do this. The directory /mnt/floppy must not be your current directory.
mount /mnt/cdrom (as user or root)
Mount a CD as user. The file /etc/fstab must be set up to do this. The directory /mnt/cdrom must not be your current directory.
umount /mnt/floppy
Unmount the floppy. The directory /mnt/floppy must not be your (or anybody else's) current working directory. Depending on your setup, you might not be able to unmount a drive that you didn't mount.
Basic Operations commands
any_command --help more
Display a brief help on a command (works with most commands). "--help" works similar to DOS "/h" switch. The "more" pipe is needed if the output is longer than one screen.
man topic
Display the contents of the system manual pages (help) on the topic. Try man man first. Press "q" to quit the viewer. The command info topic works similar and may contain more up-to-date information. Manual pages can be hard to read. Try any_command --help for short, easy to digest help on a command. If more info needed, have a look to the directory /usr/doc. To display manual page from a specific section, I may use something like in this example: man 3 exit (this displays an info on the command exit from section 3 of the manual pages).
apropos topic
Give me the list of the commands that have something to to do with my topic.
help command
Display brief info on a bash (shell) build-in command.
ls
List the content of the current directory. Under Linux, the command "dir" is an alias to ls. Many users have "ls" to be an alias to "ls --color".
ls -al more
List the content of the current directory, all files (also those starting with a dot), and in a long form. Pipe the output through the "more" command, so that the display pauses after each screenful.
cd directory
Change directory. Using "cd" without the directory name will take you to your home directory. "cd -" will take you to your previous directory and is a convenient way to toggle between two directories. "cd .." will take you one directory up.
cp source destination
Copy files. E.g., cp /home/stan/existing_file_name . will copy a file to my current working directory. Use the "-r" option (for recursive) to copy the contents of whole directories, e.g. , cp -r my_existing/dir/ ~ will copy a subdirectory under my current working directory to my home directory.
mcopy source destination
Copy a file from/to a DOS filesystem (no mounting necessary). E.g., mcopy a:\autoexec.bat ~/junk . See man mtools for related commands: mdir, mcd, mren, mmove, mdel, mmd, mrd, mformat ....
mv source destination
Move or rename files. The same command is used for moving and renaming files and directories.
ln source destination
Create a hard link called destination to the file called source. The link appears as a copy of the original files, but in reality only one copy of the file is kept, just two (or more) directory entries point to it. Any changes the file are automatically visible throughout. When one directory entry is removed, the other(s) stay(s) intact. The limitation of the hard links are: the files have to be on the same filesystem, hard links to directories or special files are impossible.
ln -s source destination
Create a symbolic (soft) link called "destination" to the file called "source". The symbolic link just specifies a path where to look for the file. In contradistinction to hard links, the source and destination don't not have to tbe on the same filesystem. In comparison to hard links, the drawback of symbolic links are: if the original file is removed, the link is "broken", symbolic links can also create circular references (like circular references in spreadsheets or databases, e.g., "a" points to "b" and "b" points back to "a").
rm files
Remove (delete) files. You must own the file in order to be able to remove it. On many systems, you will be asked or confirmation of deleation, if you don't want this, use the "-f" (=force) option, e.g., rm -f * will remove all files in my current working directory, no questions asked.
mkdir directory
Make a new directory.
rmdir directory
Remove an empty directory.
rm -r files (recursive remove)
Remove files, directories, and their subdirectories. Careful with this command as root--you can easily remove all files on the system with such a command executed on the top of your directory tree, and there is no undelete in Linux (yet). But if you really wanted to do it (reconsider), here is how (as root): rm -rf /*
cat filename more
View the content of a text file called "filename", one page a time. The "" is the "pipe" symbol (on many American keyboards it shares the key with "\") The pipe makes the output stop after each screenful. For long files, it is sometimes convenient to use the commands head and tail that display just the beginning and the end of the file. If you happened to use "cat" a binary file and your terminal displays funny characters afterwards, you can restore it with the command "reset".
less filename
Scroll through a content of a text file. Press q when done. "Less" is roughly equivalent to "more" , the command you know from DOS, although very often "less" is more convenient than "more".
pico filename
Edit a text file using the simple and standard text editor called pico.
pico -w filename Edit a text file, while disabling the long line wrap. Handy for editing configuration files, e.g. /etc/fstab.
find / -name "filename"
Find the file called "filename" on your filesystem starting the search from the root directory "/". The "filename" may contain wildcards (*,?).
locate filename
Find the file name of which contains the string "filename". Easier and faster than the previous command but depends on a database that normally rebuilds at night.
./program_name
Run an executable in the current directory, which is not on your PATH.
touch filename Change the date/time stamp of the file filename to the current time. Create an empty file if the file does not exist.
xinit
Start a barebone X-windows server (without a windows manager).
startx
Start an X-windows server and the default windows manager. Works like typing "win" under DOS with Win3.1
startx -- :1
Start another X-windows session on the display 1 (the default is opened on display 0). You can have several GUI terminals running concurrently. Switch between them using, , etc.
xterm (in X terminal)
Run a simple X-windows terminal. Typing exit will close it. There are other, more advanced "virtual" terminals for X-windows. I like the popular ones: konsole and kvt (both come with kde) and gnome-terminal (comes with gnome). If you need something really fancy-looking, try Eterm.
xboing (in X terminal).
Very nice, old-fashioned game. Many small games/programs are probably installed on your system. I also like xboard (chess).
shutdown -h now (as root)
Shut down the system to a halt. Mostly used for a remote shutdown. Use [ctrl][alt][del] for a shutdown at the console (which can be done by any user).
halt
reboot
(as root, two commands) Halt or reboot the machine. Used for remote shutdown, simpler to type than the previous command.
Display a brief help on a command (works with most commands). "--help" works similar to DOS "/h" switch. The "more" pipe is needed if the output is longer than one screen.
man topic
Display the contents of the system manual pages (help) on the topic. Try man man first. Press "q" to quit the viewer. The command info topic works similar and may contain more up-to-date information. Manual pages can be hard to read. Try any_command --help for short, easy to digest help on a command. If more info needed, have a look to the directory /usr/doc. To display manual page from a specific section, I may use something like in this example: man 3 exit (this displays an info on the command exit from section 3 of the manual pages).
apropos topic
Give me the list of the commands that have something to to do with my topic.
help command
Display brief info on a bash (shell) build-in command.
ls
List the content of the current directory. Under Linux, the command "dir" is an alias to ls. Many users have "ls" to be an alias to "ls --color".
ls -al more
List the content of the current directory, all files (also those starting with a dot), and in a long form. Pipe the output through the "more" command, so that the display pauses after each screenful.
cd directory
Change directory. Using "cd" without the directory name will take you to your home directory. "cd -" will take you to your previous directory and is a convenient way to toggle between two directories. "cd .." will take you one directory up.
cp source destination
Copy files. E.g., cp /home/stan/existing_file_name . will copy a file to my current working directory. Use the "-r" option (for recursive) to copy the contents of whole directories, e.g. , cp -r my_existing/dir/ ~ will copy a subdirectory under my current working directory to my home directory.
mcopy source destination
Copy a file from/to a DOS filesystem (no mounting necessary). E.g., mcopy a:\autoexec.bat ~/junk . See man mtools for related commands: mdir, mcd, mren, mmove, mdel, mmd, mrd, mformat ....
mv source destination
Move or rename files. The same command is used for moving and renaming files and directories.
ln source destination
Create a hard link called destination to the file called source. The link appears as a copy of the original files, but in reality only one copy of the file is kept, just two (or more) directory entries point to it. Any changes the file are automatically visible throughout. When one directory entry is removed, the other(s) stay(s) intact. The limitation of the hard links are: the files have to be on the same filesystem, hard links to directories or special files are impossible.
ln -s source destination
Create a symbolic (soft) link called "destination" to the file called "source". The symbolic link just specifies a path where to look for the file. In contradistinction to hard links, the source and destination don't not have to tbe on the same filesystem. In comparison to hard links, the drawback of symbolic links are: if the original file is removed, the link is "broken", symbolic links can also create circular references (like circular references in spreadsheets or databases, e.g., "a" points to "b" and "b" points back to "a").
rm files
Remove (delete) files. You must own the file in order to be able to remove it. On many systems, you will be asked or confirmation of deleation, if you don't want this, use the "-f" (=force) option, e.g., rm -f * will remove all files in my current working directory, no questions asked.
mkdir directory
Make a new directory.
rmdir directory
Remove an empty directory.
rm -r files (recursive remove)
Remove files, directories, and their subdirectories. Careful with this command as root--you can easily remove all files on the system with such a command executed on the top of your directory tree, and there is no undelete in Linux (yet). But if you really wanted to do it (reconsider), here is how (as root): rm -rf /*
cat filename more
View the content of a text file called "filename", one page a time. The "" is the "pipe" symbol (on many American keyboards it shares the key with "\") The pipe makes the output stop after each screenful. For long files, it is sometimes convenient to use the commands head and tail that display just the beginning and the end of the file. If you happened to use "cat" a binary file and your terminal displays funny characters afterwards, you can restore it with the command "reset".
less filename
Scroll through a content of a text file. Press q when done. "Less" is roughly equivalent to "more" , the command you know from DOS, although very often "less" is more convenient than "more".
pico filename
Edit a text file using the simple and standard text editor called pico.
pico -w filename Edit a text file, while disabling the long line wrap. Handy for editing configuration files, e.g. /etc/fstab.
find / -name "filename"
Find the file called "filename" on your filesystem starting the search from the root directory "/". The "filename" may contain wildcards (*,?).
locate filename
Find the file name of which contains the string "filename". Easier and faster than the previous command but depends on a database that normally rebuilds at night.
./program_name
Run an executable in the current directory, which is not on your PATH.
touch filename Change the date/time stamp of the file filename to the current time. Create an empty file if the file does not exist.
xinit
Start a barebone X-windows server (without a windows manager).
startx
Start an X-windows server and the default windows manager. Works like typing "win" under DOS with Win3.1
startx -- :1
Start another X-windows session on the display 1 (the default is opened on display 0). You can have several GUI terminals running concurrently. Switch between them using
xterm (in X terminal)
Run a simple X-windows terminal. Typing exit will close it. There are other, more advanced "virtual" terminals for X-windows. I like the popular ones: konsole and kvt (both come with kde) and gnome-terminal (comes with gnome). If you need something really fancy-looking, try Eterm.
xboing (in X terminal).
Very nice, old-fashioned game. Many small games/programs are probably installed on your system. I also like xboard (chess).
shutdown -h now (as root)
Shut down the system to a halt. Mostly used for a remote shutdown. Use [ctrl][alt][del] for a shutdown at the console (which can be done by any user).
halt
reboot
(as root, two commands) Halt or reboot the machine. Used for remote shutdown, simpler to type than the previous command.
Saturday, April 26, 2008
Basic administration commands
printtool (as root in X-terminal)
Configuration tool for your printer(s). Settings go to the file /etc/printcap.
setup (as root)
Configure mouse, soundcard, keyboard, X-windows, system services. There are many distibution-specific configuration utilities, setup is the default on RedHat. Mandrake 7.0 offers very nice DrakConf.
linuxconfig (as root, either in text or graphical mode).
You can access and change hundreds of setting from it. Very powerful--don't change too many things at the same time, and be careful with changing entries you don't understand.
xvidtune (in X-terminal).
Adjust the settings of the graphical display for all resolutions so as to eliminate black bands, shift the display right/left/up/down, etc. (First use the knobs on your monitor to fit your text mode correctly on the screen.) To make the changes permanent, display the frequencies on the screen and transfer them to the setup file /etc/X11/XF86Config.
alias ls="ls --color=tty"
Create an alias for the command "ls" to enhance its format with color. In this example, the alias is also called "ls" and the "color" option is only envoke when the output is done to a terminal (not to files). Put the alias into the file /etc/bashrc if you would like the alias to be always accessible to all users on the system. Type "alias" alone to see the list of aliases on your system.
adduser user_name
Create a new account (you must be root). E.g., adduser barbara Don't forget to set up the password for the new user in the next step. The user home directory is /home/user_name.
useradd user_name
The same as the command " adduser user_name ".
userdel user_name
Remove an account (you must be a root). The user's home directory and the undelivered mail must be dealt with separately (manually because you have to decide what to do with the files).
groupadd group_name
Create a new group on your system. Non-essential but can be handy even on a home machine with a small number of users.
passwd
Change the password on your current account. If you are root, you can change the password for any user using: passwd user_name
chmod perm filename (=change mode)
Change the file access permission for the files you own (unless you are root in which case you can change any file). You can make a file accessible in three modes: read (r), write (w), execute (x) to three classes of users: owner (u), members of the same group as the owner (g), others on the system (o). Check the current access permissions using: ls -l filename If the file is accessible to all users in all modes it will show: rwxrwxrwx The first triplet shows the file permission for the owner of the file, the second for his/her group, the third for others. A "no" permission is shown as "-". E.g., this command will add the permission to read the file "junk" to all (=user+group+others): chmod a+r junk This command will remove the permission to execute the file junk from others: chmod o-x junk Also try here for more info. You can set the default file permissions for the news files that you create using the command umask (see man umask).
chown new_ownername filename chgrp new_groupname filename
Change the file owner and group. You should use these two commands after you copy a file for use by somebody else.
su (=substitute user id)
Assume the superuser (=root) identity (you will be prompted for the password). Type "exit" to return you to your previous login. Don't habitually work on your machine as root. The root account is for administration and the su command is to ease your access to the administration account when you require it. You can also use "su" to assume any other user identity, e.g. su barbara will make me "barbara" (password required unless I am a superuser).
kernelcfg (as root in X terminal).
GUI to to add/remove kernel modules. You can do the same from the command line using the command "insmod", but "insmode" is less "newbie-friendly".
lsmod
List currently loaded kernel modules. A module is like a device driver--it provides operating system kernel support for a particular piece of hardware or feature.
modprobe -l more
List all the modules available for your kernel. The available modules are determined by how your Linux kernel was compliled. Every possible module/feature can be compiled on linux as either "hard wired" (fast, non-removable), "module" (maybe slower, but loaded/removable on demand), or "no" (no support for this feature at all).
insmod parport insmod ppa (as root)
Insert modules into the kernel (a module is roughly an equivalent of a DOS device driver). This example shows how to insert the modules for support of the external parallel port zip drive (it appears to be a problem to get the external zip drive to work in any other way under RH6.0 ).
rmmod module_name (as root, not essential). Remove the module module_name from the kernel.
setserial /dev/cua0 port 0x03f8 irq 4 (as root)
Set a serial port to a non-standard setting. The example here shows the standard setting for the first serial port (cua0 or ttyS0). The standard PC settings for the second serial port (cua1or ttyS1) are: address of i/o port 0x02f8, irq 3. The third serial port (cua2 or ttyS2): 0x03e8, irq 4. The forth serial port (cua3 or ttyS3): 0x02e8, irq 3. Add your setting to /etc/rc.d/rc.local if you want it to be set at the boot time. See man setserial for good a overview.
fdisk (as root)
Linux hard drive partitioning utility (DOS has a utility with the same name).
cd /usr/src/linux-2.0.36 make xconfig (as root in X terminal).
Nice GUI front-end for configuration of the kernel options in preparation for compilation of your customized kernel. (The directory name contains the version of your Linux kernel so you may need to modify the directory name if your Linux kernel version is different than 2.0.36 used in this example. You also need the "Tk" interpreter and the kernel source code installed. ) The alternatives to "make xconfig" are: "make config" (runs a scripts that asks you questions in the text mode) and "make menuconfig" (runs a text-based menu-driven configuration utility). Try: less /usr/doc/HOWTO/Kernel-HOWTO for more information. After the configuration, you may choose to proceed with kernel compilation of the new kernel by issuing the following commands: make dep make zImage The last command will take some time to complete (maybe 0.5 h, depending on your hardware). It produces the file "zImage", which is your new Linux kernel. Next: make modules make modules_install Read: /usr/doc/HOWTO/Kernel-HOWTO for information on how to install the new kernel. You will probably also find it useful to read "man depmode". Configuration, compilation and installation of a new kernel is not difficult but it CAN lead to problems if you don't know what you are doing. Compilation of a kernel is a good way to test your hardware, because it involves a massive amount of computing. If your hardware is "flaky", you will most likely receive the "signal 11" error (read the beatiful /usr/doc/FAQ/txt/GCC-SIG11-FAQ). See this for details on kernel upgrade.
depmod -a (as root)
Build the module dependency table for the kernel. This can, for example, be useful after installing and booting a new kernel. Use "modprobe -a" to load the modules.
ldconfig (as root)
Re-create the bindings and the cache for the loader of dynamic libraries ("ld"). You may want to run ldconfig after an installation of new dynamically linked libraries on your system. (It is also re-run every time you boot the computer, so if you reboot you don't have to run it manually.)
mknod /dev/fd0 b 2 0 (=make node, as root)
Create a device file. This example shows how to create a device file associated with your first floppy drive and could be useful if you happened to accidentally erase it. The options are: b=block mode device (c=character mode device, p=FIFO device, u=unbuffered character mode device). The two integers specify the major and the minor device number.
fdformat /dev/fd0H1440
mkfs -c -t ext2
(=floppy disk format, two commands, as root)
Perform a low-level formatting of a floppy in the first floppy drive (/dev/fd0), high density (1440 kB). Then make a Linux filesystem (-t ext2), checking/marking bad blocks (-c ). Making the files system is an equivalent to the high-level format.
badblocks /dev/fd01440 1440 (as root)
Check a high-density floppy for bad blocks and display the results on the screen. The parameter "1440" specifies that 1440 blocks are to be checked. This command does not modify the floppy.
fsck -t ext2 /dev/hda2 (=file system check, as root)
Check and repair a filesystem. The example uses the partition hda2, filesystem type ext2.
dd if=/dev/fd0H1440 of=floppy_image
dd if=floppy_image of=/dev/fd0H1440
(two commands, dd="data duplicator") Create an image of a floppy to the file called "floppy_image" in the current directory. Then copy floppy_image (file) to another floppy disk. Works like DOS "DISKCOPY".
Configuration tool for your printer(s). Settings go to the file /etc/printcap.
setup (as root)
Configure mouse, soundcard, keyboard, X-windows, system services. There are many distibution-specific configuration utilities, setup is the default on RedHat. Mandrake 7.0 offers very nice DrakConf.
linuxconfig (as root, either in text or graphical mode).
You can access and change hundreds of setting from it. Very powerful--don't change too many things at the same time, and be careful with changing entries you don't understand.
xvidtune (in X-terminal).
Adjust the settings of the graphical display for all resolutions so as to eliminate black bands, shift the display right/left/up/down, etc. (First use the knobs on your monitor to fit your text mode correctly on the screen.) To make the changes permanent, display the frequencies on the screen and transfer them to the setup file /etc/X11/XF86Config.
alias ls="ls --color=tty"
Create an alias for the command "ls" to enhance its format with color. In this example, the alias is also called "ls" and the "color" option is only envoke when the output is done to a terminal (not to files). Put the alias into the file /etc/bashrc if you would like the alias to be always accessible to all users on the system. Type "alias" alone to see the list of aliases on your system.
adduser user_name
Create a new account (you must be root). E.g., adduser barbara Don't forget to set up the password for the new user in the next step. The user home directory is /home/user_name.
useradd user_name
The same as the command " adduser user_name ".
userdel user_name
Remove an account (you must be a root). The user's home directory and the undelivered mail must be dealt with separately (manually because you have to decide what to do with the files).
groupadd group_name
Create a new group on your system. Non-essential but can be handy even on a home machine with a small number of users.
passwd
Change the password on your current account. If you are root, you can change the password for any user using: passwd user_name
chmod perm filename (=change mode)
Change the file access permission for the files you own (unless you are root in which case you can change any file). You can make a file accessible in three modes: read (r), write (w), execute (x) to three classes of users: owner (u), members of the same group as the owner (g), others on the system (o). Check the current access permissions using: ls -l filename If the file is accessible to all users in all modes it will show: rwxrwxrwx The first triplet shows the file permission for the owner of the file, the second for his/her group, the third for others. A "no" permission is shown as "-". E.g., this command will add the permission to read the file "junk" to all (=user+group+others): chmod a+r junk This command will remove the permission to execute the file junk from others: chmod o-x junk Also try here for more info. You can set the default file permissions for the news files that you create using the command umask (see man umask).
chown new_ownername filename chgrp new_groupname filename
Change the file owner and group. You should use these two commands after you copy a file for use by somebody else.
su (=substitute user id)
Assume the superuser (=root) identity (you will be prompted for the password). Type "exit" to return you to your previous login. Don't habitually work on your machine as root. The root account is for administration and the su command is to ease your access to the administration account when you require it. You can also use "su" to assume any other user identity, e.g. su barbara will make me "barbara" (password required unless I am a superuser).
kernelcfg (as root in X terminal).
GUI to to add/remove kernel modules. You can do the same from the command line using the command "insmod", but "insmode" is less "newbie-friendly".
lsmod
List currently loaded kernel modules. A module is like a device driver--it provides operating system kernel support for a particular piece of hardware or feature.
modprobe -l more
List all the modules available for your kernel. The available modules are determined by how your Linux kernel was compliled. Every possible module/feature can be compiled on linux as either "hard wired" (fast, non-removable), "module" (maybe slower, but loaded/removable on demand), or "no" (no support for this feature at all).
insmod parport insmod ppa (as root)
Insert modules into the kernel (a module is roughly an equivalent of a DOS device driver). This example shows how to insert the modules for support of the external parallel port zip drive (it appears to be a problem to get the external zip drive to work in any other way under RH6.0 ).
rmmod module_name (as root, not essential). Remove the module module_name from the kernel.
setserial /dev/cua0 port 0x03f8 irq 4 (as root)
Set a serial port to a non-standard setting. The example here shows the standard setting for the first serial port (cua0 or ttyS0). The standard PC settings for the second serial port (cua1or ttyS1) are: address of i/o port 0x02f8, irq 3. The third serial port (cua2 or ttyS2): 0x03e8, irq 4. The forth serial port (cua3 or ttyS3): 0x02e8, irq 3. Add your setting to /etc/rc.d/rc.local if you want it to be set at the boot time. See man setserial for good a overview.
fdisk (as root)
Linux hard drive partitioning utility (DOS has a utility with the same name).
cd /usr/src/linux-2.0.36 make xconfig (as root in X terminal).
Nice GUI front-end for configuration of the kernel options in preparation for compilation of your customized kernel. (The directory name contains the version of your Linux kernel so you may need to modify the directory name if your Linux kernel version is different than 2.0.36 used in this example. You also need the "Tk" interpreter and the kernel source code installed. ) The alternatives to "make xconfig" are: "make config" (runs a scripts that asks you questions in the text mode) and "make menuconfig" (runs a text-based menu-driven configuration utility). Try: less /usr/doc/HOWTO/Kernel-HOWTO for more information. After the configuration, you may choose to proceed with kernel compilation of the new kernel by issuing the following commands: make dep make zImage The last command will take some time to complete (maybe 0.5 h, depending on your hardware). It produces the file "zImage", which is your new Linux kernel. Next: make modules make modules_install Read: /usr/doc/HOWTO/Kernel-HOWTO for information on how to install the new kernel. You will probably also find it useful to read "man depmode". Configuration, compilation and installation of a new kernel is not difficult but it CAN lead to problems if you don't know what you are doing. Compilation of a kernel is a good way to test your hardware, because it involves a massive amount of computing. If your hardware is "flaky", you will most likely receive the "signal 11" error (read the beatiful /usr/doc/FAQ/txt/GCC-SIG11-FAQ). See this for details on kernel upgrade.
depmod -a (as root)
Build the module dependency table for the kernel. This can, for example, be useful after installing and booting a new kernel. Use "modprobe -a" to load the modules.
ldconfig (as root)
Re-create the bindings and the cache for the loader of dynamic libraries ("ld"). You may want to run ldconfig after an installation of new dynamically linked libraries on your system. (It is also re-run every time you boot the computer, so if you reboot you don't have to run it manually.)
mknod /dev/fd0 b 2 0 (=make node, as root)
Create a device file. This example shows how to create a device file associated with your first floppy drive and could be useful if you happened to accidentally erase it. The options are: b=block mode device (c=character mode device, p=FIFO device, u=unbuffered character mode device). The two integers specify the major and the minor device number.
fdformat /dev/fd0H1440
mkfs -c -t ext2
(=floppy disk format, two commands, as root)
Perform a low-level formatting of a floppy in the first floppy drive (/dev/fd0), high density (1440 kB). Then make a Linux filesystem (-t ext2), checking/marking bad blocks (-c ). Making the files system is an equivalent to the high-level format.
badblocks /dev/fd01440 1440 (as root)
Check a high-density floppy for bad blocks and display the results on the screen. The parameter "1440" specifies that 1440 blocks are to be checked. This command does not modify the floppy.
fsck -t ext2 /dev/hda2 (=file system check, as root)
Check and repair a filesystem. The example uses the partition hda2, filesystem type ext2.
dd if=/dev/fd0H1440 of=floppy_image
dd if=floppy_image of=/dev/fd0H1440
(two commands, dd="data duplicator") Create an image of a floppy to the file called "floppy_image" in the current directory. Then copy floppy_image (file) to another floppy disk. Works like DOS "DISKCOPY".
Friday, April 25, 2008
Soto Betawi Asli
BAHAN :
1 kilo daging sapi kalau suka bisa pake jeroan sapi ataupun kaki sapi.
1 lengkuas gepruk.
1 sereh.
3 lembar daun salam.
Rebus bahan-bahan diatas dengan air, buang terus kotoran daging yang keluar.
Setelah daging empuk, kecilkan api.
BUMBU :
5 bawang merah.
3 bawang putih.
1 ruas jempol jahe.
1 sdm ketumbar.
1/2 sdt jinten.
lada butir secukupnya.
Haluskan semua bumbu diatas.
BAHAN LAINNYA :
1 kotak kecil santan kara.
1/2 liter susu sapi segar atau susu ultra tawar.
kentang kupas, belah 2 goreng.
tomat.
daun bawang prei diiris.
jeruk sambal.
emping goreng.
bawang goreng.
CARA MEMBUAT :
1. Didihkan kaldu daging, masukkan bumbu halus (tidak perlu di tumis).
2. Tambahkan garam, rasakan. Kalau suka boleh tambah bumbu penyedap secukupnya.
3. Tambah santan kara dan susu cair.
4. Udah jadi deh kuahnya.
CARA PENYAJIAN :
1. Potong / iris kentang ke dalam mangkok.
2. Tambahkan irisan tomat.
3. Taburin dengan daun bawang.
4. Tambah bawang goreng.
5. Tambah kecap manis BANGO.
6. Tambah merica bubuk (kalau suka).
7. Tuangi kuah sotonya.
8. Tambah emping goreng dan peres 1/2 jeruk sambal.
Sajikan dengan nasi yang atasnya sudah ditaburin bawang goreng...
Lebih sedap lagi kalau dimakan dengan sambal....
1 kilo daging sapi kalau suka bisa pake jeroan sapi ataupun kaki sapi.
1 lengkuas gepruk.
1 sereh.
3 lembar daun salam.
Rebus bahan-bahan diatas dengan air, buang terus kotoran daging yang keluar.
Setelah daging empuk, kecilkan api.
BUMBU :
5 bawang merah.
3 bawang putih.
1 ruas jempol jahe.
1 sdm ketumbar.
1/2 sdt jinten.
lada butir secukupnya.
Haluskan semua bumbu diatas.
BAHAN LAINNYA :
1 kotak kecil santan kara.
1/2 liter susu sapi segar atau susu ultra tawar.
kentang kupas, belah 2 goreng.
tomat.
daun bawang prei diiris.
jeruk sambal.
emping goreng.
bawang goreng.
CARA MEMBUAT :
1. Didihkan kaldu daging, masukkan bumbu halus (tidak perlu di tumis).
2. Tambahkan garam, rasakan. Kalau suka boleh tambah bumbu penyedap secukupnya.
3. Tambah santan kara dan susu cair.
4. Udah jadi deh kuahnya.
CARA PENYAJIAN :
1. Potong / iris kentang ke dalam mangkok.
2. Tambahkan irisan tomat.
3. Taburin dengan daun bawang.
4. Tambah bawang goreng.
5. Tambah kecap manis BANGO.
6. Tambah merica bubuk (kalau suka).
7. Tuangi kuah sotonya.
8. Tambah emping goreng dan peres 1/2 jeruk sambal.
Sajikan dengan nasi yang atasnya sudah ditaburin bawang goreng...
Lebih sedap lagi kalau dimakan dengan sambal....
Wednesday, April 23, 2008
Process Control commands
ps (=print status)
Display the list of currently running processes with their process IDs (PID) numbers. Use ps axu to see all processes currently running on your system (also those of other users or without a controlling terminal), each with the name of the owner. Use "top" to keep listing the processes currently running.
fg PID
Bring a background or stopped process to the foreground.
bg PID
Send the process to the background. Opposite to fg. The same can be accomplished withz. If you have stopped jobs, you have to type exit twice in row to log out.
any_command&
Run any command in the background (the symbol "&" means "run the proceeding command in the background").
batch any_command
Run any command (usually one that is going to take more time) when the system load is low. I can logout, and the process will keep running.
at 17:00
Execute a command at a specified time. You will be prompted for the command(s) to run, until you pressd.
kill PID
Force a process shutdown. First determine the PID of the process to kill using ps.
killall program_name
Kill program(s) by name.
xkill (in an xwindow terminal)
Kill a GUI-based program with mouse. (Point with your mouse cursor at the window of the process you want to kill and click.)
lpc (as root)
Check and control the printer(s). Type "?" to see the list of available commands.
lpq
Show the content of the printer queue. Under KDE (X-Windows), you may use GUI-based "Printer Queue" available from "K"menu-Utilities.
lprm job_number
Remove a printing job "job_number" from the queue.
nice program_name
Run program_name adjusting its priority. Since the priority is not specified in this example, it will be adjusted by 10 (the process will run slower), from the default value (usually 0). The lower the number (of "niceness" to other users on the system), the higher the priority. The priority value may be in the range -20 to 19. Only root may specify negative values. Use "top" to display the priorities of the running processes.
renice -1 PID (as root)
Change the priority of a running process to -1. Normal users can only adjust processes they own, and only up from the current value (make them run slower).
[ctrl]c, [ctrl]z, [ctrl]s, and [ctrl]q also belong to this chapter but they were described previously. In short they mean: stop the current command, send the current command to the background, stop the data transfer, resume the data transfer.
Display the list of currently running processes with their process IDs (PID) numbers. Use ps axu to see all processes currently running on your system (also those of other users or without a controlling terminal), each with the name of the owner. Use "top" to keep listing the processes currently running.
fg PID
Bring a background or stopped process to the foreground.
bg PID
Send the process to the background. Opposite to fg. The same can be accomplished with
any_command&
Run any command in the background (the symbol "&" means "run the proceeding command in the background").
batch any_command
Run any command (usually one that is going to take more time) when the system load is low. I can logout, and the process will keep running.
at 17:00
Execute a command at a specified time. You will be prompted for the command(s) to run, until you press
kill PID
Force a process shutdown. First determine the PID of the process to kill using ps.
killall program_name
Kill program(s) by name.
xkill (in an xwindow terminal)
Kill a GUI-based program with mouse. (Point with your mouse cursor at the window of the process you want to kill and click.)
lpc (as root)
Check and control the printer(s). Type "?" to see the list of available commands.
lpq
Show the content of the printer queue. Under KDE (X-Windows), you may use GUI-based "Printer Queue" available from "K"menu-Utilities.
lprm job_number
Remove a printing job "job_number" from the queue.
nice program_name
Run program_name adjusting its priority. Since the priority is not specified in this example, it will be adjusted by 10 (the process will run slower), from the default value (usually 0). The lower the number (of "niceness" to other users on the system), the higher the priority. The priority value may be in the range -20 to 19. Only root may specify negative values. Use "top" to display the priorities of the running processes.
renice -1 PID (as root)
Change the priority of a running process to -1. Normal users can only adjust processes they own, and only up from the current value (make them run slower).
[ctrl]c, [ctrl]z, [ctrl]s, and [ctrl]q also belong to this chapter but they were described
Tuesday, April 22, 2008
Network Application commands
netscape (in X terminal)
Run netscape (requires a separate Netscape installation). The current versions of Netscape (4.x) are known to be big and buggy. They occasionally crash by vanishing (no other harm done). Also, when not connected to the network , Netscape likes to refuse to do anything (looks like it hanged)-it revives when you connect.
netscape -display host:0.0 (in X terminal)
Run netscape on the current machine and direct the output to machine named "host" display 0 screen 0. Your current machine must have a permission to display on the machine "host" (typically given by executing the command xhost current_machine_name in the xterminal of the machine host. Other X-windows program can be run remotely the same way.
lynx file.html
View an html file or browse the net from the text mode.
pine
A good text-mode mail reader. Another good and standard one is elm. Your Netscape mail will read the mail from your Internet account. pine will let you read the "local" mail, e.g. the mail your son or a cron process sends to you from a computer on your home network. The command mail could also be used for reading/composing mail, but it would be inconvenient--it is meant to be used in scripts for automation.
elm
A good tex-mode mail reader. See the previous command.
mutt
A really basic but extremally useful and fast mail reader.
mail
A basic operating system tool for e-mail. Look at the previous commands for a better e-mail reader. mail is good if you wanted to send an e-mail from a shell script.
licq (in X term)
An icq "instant messaging" client. Another good one is kxicq. Older distributions don't have an icq client installed, you have to do download one and install it.
talk username1
Talk to another user currently logged on your machine (or use "talk username1@machinename" to talk to a user on a different computer) . To accept the invitation to the conversation, type the command "talk username2". If somebody is trying to talk to you and it disrupts your work, your may use the command "mesg n" to refuse accepting messages. You may want to use "who" or "rwho" to determine the users who are currently logged-in.
mc
Launch the "Midnight Commander" file manager (looks like "Norton Commander" for Linux).
telnet server Connect to another machine using the TELNET protocol. Use a remote machine name or IP address. You will be prompted for your login name and password--you must have an account on the remote machine to login. Telnet will connect you to another machine and let you operate on it as if you were sitting at its keyboard (almost). Telnet is not very secure--everything you type goes in open text, even your password!
rlogin server (=remote login)
Connect to another machine. The login name/password from your current session is used; if it fails you are prompted for a password.
rsh server (=remote shell)
Yet another way to connect to a remote machine. The login name/password from your current session is used; if it fails you are prompted for a password.
ftp server
Ftp another machine. (There is also ncftp which adds extra features and gftp for GUI .) Ftp is good for copying files to/from a remote machine. Try user "anonymous" if you don't have an account on the remote server. After connection, use "?" to see the list of available ftp commands. The essential ftp command are: ls (see the files on the remote system), ASCII, binary (set the file transfer mode to either text or binary, important that you select the proper one ), get (copy a file from the remote system to the local system), mget (get many files at once), put (copy a file from the local system to the remote system), mput (put many files at once), bye (disconnect). For automation in a script, you may want to use ncftpput and ncftpget, for example: ncftpput -u my_user_name -p my_password -a remote.host.domain remote_dir *local.html
minicom
Minicom program (looks like "Procomm for Linux").
Run netscape (requires a separate Netscape installation). The current versions of Netscape (4.x) are known to be big and buggy. They occasionally crash by vanishing (no other harm done). Also, when not connected to the network , Netscape likes to refuse to do anything (looks like it hanged)-it revives when you connect.
netscape -display host:0.0 (in X terminal)
Run netscape on the current machine and direct the output to machine named "host" display 0 screen 0. Your current machine must have a permission to display on the machine "host" (typically given by executing the command xhost current_machine_name in the xterminal of the machine host. Other X-windows program can be run remotely the same way.
lynx file.html
View an html file or browse the net from the text mode.
pine
A good text-mode mail reader. Another good and standard one is elm. Your Netscape mail will read the mail from your Internet account. pine will let you read the "local" mail, e.g. the mail your son or a cron process sends to you from a computer on your home network. The command mail could also be used for reading/composing mail, but it would be inconvenient--it is meant to be used in scripts for automation.
elm
A good tex-mode mail reader. See the previous command.
mutt
A really basic but extremally useful and fast mail reader.
A basic operating system tool for e-mail. Look at the previous commands for a better e-mail reader. mail is good if you wanted to send an e-mail from a shell script.
licq (in X term)
An icq "instant messaging" client. Another good one is kxicq. Older distributions don't have an icq client installed, you have to do download one and install it.
talk username1
Talk to another user currently logged on your machine (or use "talk username1@machinename" to talk to a user on a different computer) . To accept the invitation to the conversation, type the command "talk username2". If somebody is trying to talk to you and it disrupts your work, your may use the command "mesg n" to refuse accepting messages. You may want to use "who" or "rwho" to determine the users who are currently logged-in.
mc
Launch the "Midnight Commander" file manager (looks like "Norton Commander" for Linux).
telnet server Connect to another machine using the TELNET protocol. Use a remote machine name or IP address. You will be prompted for your login name and password--you must have an account on the remote machine to login. Telnet will connect you to another machine and let you operate on it as if you were sitting at its keyboard (almost). Telnet is not very secure--everything you type goes in open text, even your password!
rlogin server (=remote login)
Connect to another machine. The login name/password from your current session is used; if it fails you are prompted for a password.
rsh server (=remote shell)
Yet another way to connect to a remote machine. The login name/password from your current session is used; if it fails you are prompted for a password.
ftp server
Ftp another machine. (There is also ncftp which adds extra features and gftp for GUI .) Ftp is good for copying files to/from a remote machine. Try user "anonymous" if you don't have an account on the remote server. After connection, use "?" to see the list of available ftp commands. The essential ftp command are: ls (see the files on the remote system), ASCII, binary (set the file transfer mode to either text or binary, important that you select the proper one ), get (copy a file from the remote system to the local system), mget (get many files at once), put (copy a file from the local system to the remote system), mput (put many files at once), bye (disconnect). For automation in a script, you may want to use ncftpput and ncftpget, for example: ncftpput -u my_user_name -p my_password -a remote.host.domain remote_dir *local.html
minicom
Minicom program (looks like "Procomm for Linux").
Tuesday, April 15, 2008
Common Linux commands -- system info
pwd
Print working directory, i.e., display the name of my current directory on the screen.
hostname
Print the name of the local host (the machine on which you are working). Use netconf (as root) to change the name of the machine.
whoami
Print my login name.
id username
Print user id (uid) and his/her group id (gid), effective id (if different than the real id) and the supplementary groups.
date
Print or change the operating system date and time. E.g., I could change the date and time to 2000-12-31 23:57 using this command: date 123123572000 To set the hardware (BIOS) clock from the system (Linux) clock, use the command (as root) setclock
time
Determine the amount of time that it takes for a process to complete + other info. Don't confuse it with the date command. E.g. I can find out how long it takes to display a directory content using: time ls
who
Determine the users logged on the machine.
rwho -a (=remote who)
Determine all users logged on your network. The rwho service must be enabled for this command to run. If it isn't, run setup as root to enable "rwho".
finger user_name
System info about a user. Try: finger root
last
Show listing of users last logged-in on your system.
history more
Show the last (1000 or so) commands executed from the command line on the current account. The " more" causes the display to stop after each screenful.
uptime
Show the amount of time since the last reboot.
ps (=print status)
List the processes currently run by the current user.
ps axu more
List all the processes currently running, even those without the controlling terminal, together with the name of the user that owns each process.
top
Keep listing the currently running processes, sorted by cpu usage (top users first). In KDE, you can get GUI-based Ktop from "K"menu under "System"-"Task Manager" (or by executing "ktop" in an X-terminal).
uname -a (= Unix name with option "all")
Info on your (local) server. I can also use guname (in X-window terminal) to display the info more nicely.
free
Memory info (in kilobytes).
df -h (=disk free)
Print disk info about all the filesystems (in human-readable form)
du / -bh more (=disk usage) Print detailed disk usage for each subdirectory starting at the "/" (root) directory (in human legible form).
cat /proc/cpuinfo
Cpu info--it show the content of the file cpuinfo. Note that the files in the /proc directory are not real files--they are hooks to look at information available to the kernel.
cat /proc/interrupts
List the interrupts in use.
cat /proc/version
Linux version and other info
cat /proc/filesystems
Show the types of filesystems currently in use.
cat /etc/printcap
Show the setup of printers.
lsmod
(As root. Use /sbin/lsmod to execute this command when you are a non-root user.) Show the kernel modules currently loaded.
setmore
Show the current user environment.
echo $PATH
Show the content of the environment variable "PATH". This command can be used to show other environment variables as well. Use "set" to see the full environment.
dmesg less
Print kernel messages (the content of the so-called kernel ring buffer). Press "q" to quit "less". Use less /var/log/dmesg to see what "dmesg" dumped into this file right after the last system bootup.
Print working directory, i.e., display the name of my current directory on the screen.
hostname
Print the name of the local host (the machine on which you are working). Use netconf (as root) to change the name of the machine.
whoami
Print my login name.
id username
Print user id (uid) and his/her group id (gid), effective id (if different than the real id) and the supplementary groups.
date
Print or change the operating system date and time. E.g., I could change the date and time to 2000-12-31 23:57 using this command: date 123123572000 To set the hardware (BIOS) clock from the system (Linux) clock, use the command (as root) setclock
time
Determine the amount of time that it takes for a process to complete + other info. Don't confuse it with the date command. E.g. I can find out how long it takes to display a directory content using: time ls
who
Determine the users logged on the machine.
rwho -a (=remote who)
Determine all users logged on your network. The rwho service must be enabled for this command to run. If it isn't, run setup as root to enable "rwho".
finger user_name
System info about a user. Try: finger root
last
Show listing of users last logged-in on your system.
history more
Show the last (1000 or so) commands executed from the command line on the current account. The " more" causes the display to stop after each screenful.
uptime
Show the amount of time since the last reboot.
ps (=print status)
List the processes currently run by the current user.
ps axu more
List all the processes currently running, even those without the controlling terminal, together with the name of the user that owns each process.
top
Keep listing the currently running processes, sorted by cpu usage (top users first). In KDE, you can get GUI-based Ktop from "K"menu under "System"-"Task Manager" (or by executing "ktop" in an X-terminal).
uname -a (= Unix name with option "all")
Info on your (local) server. I can also use guname (in X-window terminal) to display the info more nicely.
free
Memory info (in kilobytes).
df -h (=disk free)
Print disk info about all the filesystems (in human-readable form)
du / -bh more (=disk usage) Print detailed disk usage for each subdirectory starting at the "/" (root) directory (in human legible form).
cat /proc/cpuinfo
Cpu info--it show the content of the file cpuinfo. Note that the files in the /proc directory are not real files--they are hooks to look at information available to the kernel.
cat /proc/interrupts
List the interrupts in use.
cat /proc/version
Linux version and other info
cat /proc/filesystems
Show the types of filesystems currently in use.
cat /etc/printcap
Show the setup of printers.
lsmod
(As root. Use /sbin/lsmod to execute this command when you are a non-root user.) Show the kernel modules currently loaded.
setmore
Show the current user environment.
echo $PATH
Show the content of the environment variable "PATH". This command can be used to show other environment variables as well. Use "set" to see the full environment.
dmesg less
Print kernel messages (the content of the so-called kernel ring buffer). Press "q" to quit "less". Use less /var/log/dmesg to see what "dmesg" dumped into this file right after the last system bootup.
Saturday, March 15, 2008
Cumi Panggang
Bahan:
500 gr cumi ukuran besar, bersihkan, kerat-kerat.
4 siung bawang putih, keprek, cincang kasar.
4 sdm saus hoisin.
2 sdm madu.
2 sdm saus tomat.
2 sdm saus cabai.
1 sdt minyak wijen.
2 btg daun bawang, iris tipis.
500 gr cumi ukuran besar, bersihkan, kerat-kerat.
4 siung bawang putih, keprek, cincang kasar.
4 sdm saus hoisin.
2 sdm madu.
2 sdm saus tomat.
2 sdm saus cabai.
1 sdt minyak wijen.
2 btg daun bawang, iris tipis.
Cara membuat:
1. Campur bawang putih, saus hoisin, madu, saus tomat, saus cabai, minyak wijen, dan daun bawang, aduk rata.
2. Masukkan cumi, aduk rata. Diamkan dalam lemari es selama 15 menit.
3. Bakar cumi di atas bara api sampai berwarna kecokelatan. Sajikan.
Untuk 6 orang
2. Masukkan cumi, aduk rata. Diamkan dalam lemari es selama 15 menit.
3. Bakar cumi di atas bara api sampai berwarna kecokelatan. Sajikan.
Untuk 6 orang
Tip: Untuk membuat BBQ ikan, ayam, atau daging, usahakan merendamnya dalam bumbu lebih lama, agar bumbu lebih meresap.
Monday, February 25, 2008
Mempercepat DNS-Lookup Proses
Disaat anda browsing internet entah itu menggunakan browser apapun mungkin anda pernah memperhatikan tulisan di kiri bawah baris status browser? “Connecting to…”, “Waiting for…”, “Transfering data from…”. Itu semua adalah merupakan komunikasi data yang terjadi antara browser, server DNS, dan website yang sedang anda kunjungi. Kalau anda ingin proses tersebut bisa berjalan lebih cepat, ada sedikit tips yang sebenarnya anda bisa lakukan untuk mempercepat proses tersebut.
Ketika kita mengunjungi sebuah website, misalnya www.yahoo.com, yang pertama kali dilakukan oleh browser adalah meminta alamat IP dari website yahoo ke server DNS. Server DNS ini kemudian melakukan pencarian ke database dan memberikan hasilnya kebrowser anda. Alamat IP dari website yahoo adalah 206.190.60.37, selanjutnya browser meminta halaman yang ingin anda kunjungi ke alamat ini. Proses permintaan alamat IP dan pencarian di database jelas memerlukan waktu.
Ada satu trik agar agar browser tidak perlu bertanya ke server DNS yaitu dengan mencantumkan alamat IP website yahoo tersebut ke dalam file Hosts yang terdapat di folder C:Windows\System32\Driver\etc. Dengan cara tersebut browser akan langsung meminta halaman web ke alamat 206.190.60.37.
Cantumkan semua alamat website yang sering anda kunjungi ke dalam file hosts, kalau anda bingung untuk mengetahui alamat IP dari masing-masing website, bisa gunakan perintah run kemudian ketikkan perintah ping www.yahoo.com. Alamat website silahkan diganti dengan website yang anda ingin tahu alamat IP nya. Setelah semua alamat IP yang sering anda kunjungi anda masukan ke file hosts, restart windows agar system membaca ulang isi file hosts. File hosts juga bisa digunakan untuk memblokir alamat-alamat website yang tidak diinginkan.
Catatan : untuk membuka file hosts bisa digunakan program notepad, penulisannya adalah anda tuliskan dahulu nomer IP nya kemudian spasi alamat websitenya.
Ketika kita mengunjungi sebuah website, misalnya www.yahoo.com, yang pertama kali dilakukan oleh browser adalah meminta alamat IP dari website yahoo ke server DNS. Server DNS ini kemudian melakukan pencarian ke database dan memberikan hasilnya kebrowser anda. Alamat IP dari website yahoo adalah 206.190.60.37, selanjutnya browser meminta halaman yang ingin anda kunjungi ke alamat ini. Proses permintaan alamat IP dan pencarian di database jelas memerlukan waktu.
Ada satu trik agar agar browser tidak perlu bertanya ke server DNS yaitu dengan mencantumkan alamat IP website yahoo tersebut ke dalam file Hosts yang terdapat di folder C:Windows\System32\Driver\etc. Dengan cara tersebut browser akan langsung meminta halaman web ke alamat 206.190.60.37.
Cantumkan semua alamat website yang sering anda kunjungi ke dalam file hosts, kalau anda bingung untuk mengetahui alamat IP dari masing-masing website, bisa gunakan perintah run kemudian ketikkan perintah ping www.yahoo.com. Alamat website silahkan diganti dengan website yang anda ingin tahu alamat IP nya. Setelah semua alamat IP yang sering anda kunjungi anda masukan ke file hosts, restart windows agar system membaca ulang isi file hosts. File hosts juga bisa digunakan untuk memblokir alamat-alamat website yang tidak diinginkan.
Catatan : untuk membuka file hosts bisa digunakan program notepad, penulisannya adalah anda tuliskan dahulu nomer IP nya kemudian spasi alamat websitenya.
Friday, February 22, 2008
Menghindari Hacking Pada Blog
Tidak jarang seorang blogger merasa khawatir di hack, apalagi dengan semakin popular sebuah website, akan semakin sering terekspose dan mendapat ancaman hack. Untuk menghindari bahaya tersebut, berikut ini adalah beberapa tips guna menghindari instalasi wordpress kamu dari serangan hack.
Amankan Database
Saran pertama yang saya anjurkan adalah amankan database website atau blog kamu. Caranya, buat backup database dan sering seringlah melakukan backup data. Kamu dapat melakukannya melalui phpMyAdmin dalam account hosting, atau menggunakan plugins, seperti WP-Database Backup (http://wordpress.org/extend/plugins/wp-db-backup/). Plugins ini melakukan tugas backup menjadi lebih mudah. Kamu hanya perlu login ke admin panel WordPress, lalu klik beberapa link. Plugins ini patut dimiliki oleh setiap blogger.
Scan WordPress
Setelah memiliki plugin yang melindungi database website, langkah selanjutnya adalah men-scan untuk memastikan pada instalasi WordPress tidak dijumpai adanya celah pada keamanan. Tugas ini dapat dilakukan juga dengan menggunakan plugin yang disebut WP Security Scan (http://wordpress.org/extend/plugins/wp-security-scan/). Dengan plugin ini kamu dapat mengedintifikasi celah – celah keamanan jika dijumpai pada blog. Selain itu kita akan diberitahu cara memperbaikinya. Plugins WP Security Scan juga akan menawarkan untuk penggantian nama tables prefixes, menguji kekuatan password, menghapus account admin dan melakukan verifikasi directory blog agar memiliki keamanan yang baik.
Tangkal Penyusup
Penyusup dalam pengertian ini adalah kombinasi dari huruf, angka dan sebagainya yang berusaha untuk menemukan password kamu. Bahkan script Python bias dipakai untuk mencoba menemukan password blog WordPress kamu. Akan sangat mudah bagi penyusup menemukan password bila kamu menggunakan nama blog atau kata yang mudah ditebak. Oleh karena itu, usahakan menggunakan password yang benar – benar kuat, menggunakan kombinasi huruf kecil huruf besar, angka serta karakter khusus. Kamu pun bias memanfaatkan generator password dalam WP Security Scan untuk membuat password yang kuat.Meskipun menggunakan password yang juat adalah trik yang baik, cara lain yang akan memberikan perlindungan effisien bagi blog kamu, yaitu dengan menambah Apache Login form ke WP-Admin directory. Ask Apache (WP Security Scan) plugin berguna untuk melindungi wp-admin directory yang keamanan nya setara dengan authentication server level (htpasswd). Plugin ini memungkinkan kamu mendisable hotlinking, atau mencegah akses langsung ke directory wp-content dan wp-includes.
Cermati Plugins
Tidak semua plugins itu bagus, ada diantaranya yang merupakan mata – mata untuk mengetahui celah keamanan yang terdapat dalam blog kamu. Karena alasan ini, maka ada perlunya kamu menyembunyikan konten directory /wp-content/plugins. Caranya adalah dengan membuat file kosong yang diberi nama index.html, yang kemudian diupload ke directory wp-content/plugins.
Amankan Database
Saran pertama yang saya anjurkan adalah amankan database website atau blog kamu. Caranya, buat backup database dan sering seringlah melakukan backup data. Kamu dapat melakukannya melalui phpMyAdmin dalam account hosting, atau menggunakan plugins, seperti WP-Database Backup (http://wordpress.org/extend/plugins/wp-db-backup/). Plugins ini melakukan tugas backup menjadi lebih mudah. Kamu hanya perlu login ke admin panel WordPress, lalu klik beberapa link. Plugins ini patut dimiliki oleh setiap blogger.
Scan WordPress
Setelah memiliki plugin yang melindungi database website, langkah selanjutnya adalah men-scan untuk memastikan pada instalasi WordPress tidak dijumpai adanya celah pada keamanan. Tugas ini dapat dilakukan juga dengan menggunakan plugin yang disebut WP Security Scan (http://wordpress.org/extend/plugins/wp-security-scan/). Dengan plugin ini kamu dapat mengedintifikasi celah – celah keamanan jika dijumpai pada blog. Selain itu kita akan diberitahu cara memperbaikinya. Plugins WP Security Scan juga akan menawarkan untuk penggantian nama tables prefixes, menguji kekuatan password, menghapus account admin dan melakukan verifikasi directory blog agar memiliki keamanan yang baik.
Tangkal Penyusup
Penyusup dalam pengertian ini adalah kombinasi dari huruf, angka dan sebagainya yang berusaha untuk menemukan password kamu. Bahkan script Python bias dipakai untuk mencoba menemukan password blog WordPress kamu. Akan sangat mudah bagi penyusup menemukan password bila kamu menggunakan nama blog atau kata yang mudah ditebak. Oleh karena itu, usahakan menggunakan password yang benar – benar kuat, menggunakan kombinasi huruf kecil huruf besar, angka serta karakter khusus. Kamu pun bias memanfaatkan generator password dalam WP Security Scan untuk membuat password yang kuat.Meskipun menggunakan password yang juat adalah trik yang baik, cara lain yang akan memberikan perlindungan effisien bagi blog kamu, yaitu dengan menambah Apache Login form ke WP-Admin directory. Ask Apache (WP Security Scan) plugin berguna untuk melindungi wp-admin directory yang keamanan nya setara dengan authentication server level (htpasswd). Plugin ini memungkinkan kamu mendisable hotlinking, atau mencegah akses langsung ke directory wp-content dan wp-includes.
Cermati Plugins
Tidak semua plugins itu bagus, ada diantaranya yang merupakan mata – mata untuk mengetahui celah keamanan yang terdapat dalam blog kamu. Karena alasan ini, maka ada perlunya kamu menyembunyikan konten directory /wp-content/plugins. Caranya adalah dengan membuat file kosong yang diberi nama index.html, yang kemudian diupload ke directory wp-content/plugins.
Friday, February 15, 2008
Atasi Knalpot Mbrebet Pada FU150
Keluhan mendasar buat penunggang bebek gambot ini adalah penyakit knalpot mbrebet. Selamat mencoba.
Dari beberapa tulisan terungkap ada sedikit kelemahan yang cukup banyak dialami para pemilik baru bebek gambot ini. Keluhan yang banyak dituliskan adalah knalpot sering mbrebet di putaran bawah. Berikut ini kumpulan tips yang berhasil saya kumpulkan.
Dari beberapa tulisan terungkap ada sedikit kelemahan yang cukup banyak dialami para pemilik baru bebek gambot ini. Keluhan yang banyak dituliskan adalah knalpot sering mbrebet di putaran bawah. Berikut ini kumpulan tips yang berhasil saya kumpulkan.
- Sebelum menggenjot si gambot, pada pagi hari sebaiknya dipanaskan cukup lama sebutlah 5 menit. Tapi kan lumayan dari pada nanti mati sendiri, ya nggak?
- Ini tips paling canggih versi bro Sumantri dari Chips Motor. Gantilah pilot jet standar 12,5 dengan pilot jet 17,5. Jangan lupa sesuaikan stelan air screw dari semula ½ putaran kalau pake 12,5 jadi 1 putaran berlawanan arah jarum jam. Patokan pilot jet bergantung pula kondisi suhu harian motor dipakai. Bro Mantri menyarankan kalau untuk daerah dingin macam Bandung pakai pilot jet 15 dengan stelan air screw ¾ putaran.
- Tips hemat nih, kalau males beli pilot jet 17,5 rojok aja yg standar biar rada gedean trus rapetin deh busi standard bawaan motor sekitar 0,7 mm. Selebihnya setting lagi air screw (btw, ternyata kata mekaniknya ini bukan buat setelan angin tapi setelan pasokan bensin, jadi kudu pas bener!!).
Satria FU150 Mati Mesin Saat Hujan
Banyak yang mengatakan bahwa Suzuki Satria F150 itu paling takut terhadap air!
Ternyata memang banyak sekali yang mengalami masalah mesin mati pada Satria F150 nya karena terkena air. Sudah hampir bisa dipastikan bahwa mesin mati karena air itu dikarenakan busi tidak dapat memantik api karena terhalang oleh air ataupun udara yang kadar airnya sangat tinggi (lembab).
Ada beberapa cara yang biasanya dilakukan oleh rekan saya sebagai solusi. Misalnya dengan menambahkan pita perekat isolator pada cap (chop) busi, atau mengganti karet chop busi yang sudah getas (rengat dan retak). Cara ini memang sangat dianjurkan karena lebih melindungi busi dari resiko masuknya air. Cara lain yang menurut saya agak ekstrim adalah menambah sekat penutup dari bahan karet, plastik atau lain - lain, dibentuk sedemikian rupa sehingga lubang busi terlindung dari cipratan air. Saya kira cara ini bagus tetapi dilihat dari sudut estetika keindahan, sangat kurang.
Sebagian besar yang sudah melakukan usaha tersebut mengalami kesuksesan, motornya bisa terus melaju menembus hujan badai. Namun beberapanya masih tetap kecewa, karena mesinnya tetap mati terkena air.
Artikel saya ini mungkin tidak menawarkan solusi yang tepat, tetapi bersifat mengingatkan bahwa masih ada satu bagian lagi yang banyak orang lupa atau bahkan tidak tahu. Tepat di bawah pangkal pipa knalpot ada sebuah lubang kecil yang dibuat dengan tujuan sebagai saluran pembuangan air apabila air masuk dari atas (lubang busi). Tujuannya sebenarnya bagus, tapi sayang lubang ini pun sering tersumbat lumpur yang terpental dari ban depan karena arah lubang ini memang sejajar dengan ban depan.
Gambar di atas adalah posisi lubang saluran pembuangan air. Mudah - mudahan bisa dijadikan patokan untuk mencari posisi lubang tersebut.
Cara membersihkannya mudah, bisa dengan tusuk gigi, kawat keras atau sedotan air mineral kemasan gelas plastik. Yang penting bisa masuk ke lubang tersebut. Kedalaman lubang kira - kira sekitar 8 cm, atau kira - kira sampai ke tengah dalam mesin. Jadi ketika Anda memasukkan tongkat media pembersihnya, bisa dikira - kira seberapa dalam nantinya sampai saat Anda selesai membersihkan lubang.
Baiknya lubang ini selalu diperiksa secara berkala, terutama untuk motor yang sering melewati jalan basah, jalan berlumpur (becek) atau sering terkena hujan.
Ternyata memang banyak sekali yang mengalami masalah mesin mati pada Satria F150 nya karena terkena air. Sudah hampir bisa dipastikan bahwa mesin mati karena air itu dikarenakan busi tidak dapat memantik api karena terhalang oleh air ataupun udara yang kadar airnya sangat tinggi (lembab).
Ada beberapa cara yang biasanya dilakukan oleh rekan saya sebagai solusi. Misalnya dengan menambahkan pita perekat isolator pada cap (chop) busi, atau mengganti karet chop busi yang sudah getas (rengat dan retak). Cara ini memang sangat dianjurkan karena lebih melindungi busi dari resiko masuknya air. Cara lain yang menurut saya agak ekstrim adalah menambah sekat penutup dari bahan karet, plastik atau lain - lain, dibentuk sedemikian rupa sehingga lubang busi terlindung dari cipratan air. Saya kira cara ini bagus tetapi dilihat dari sudut estetika keindahan, sangat kurang.
Sebagian besar yang sudah melakukan usaha tersebut mengalami kesuksesan, motornya bisa terus melaju menembus hujan badai. Namun beberapanya masih tetap kecewa, karena mesinnya tetap mati terkena air.
Artikel saya ini mungkin tidak menawarkan solusi yang tepat, tetapi bersifat mengingatkan bahwa masih ada satu bagian lagi yang banyak orang lupa atau bahkan tidak tahu. Tepat di bawah pangkal pipa knalpot ada sebuah lubang kecil yang dibuat dengan tujuan sebagai saluran pembuangan air apabila air masuk dari atas (lubang busi). Tujuannya sebenarnya bagus, tapi sayang lubang ini pun sering tersumbat lumpur yang terpental dari ban depan karena arah lubang ini memang sejajar dengan ban depan.
Gambar di atas adalah posisi lubang saluran pembuangan air. Mudah - mudahan bisa dijadikan patokan untuk mencari posisi lubang tersebut.
Cara membersihkannya mudah, bisa dengan tusuk gigi, kawat keras atau sedotan air mineral kemasan gelas plastik. Yang penting bisa masuk ke lubang tersebut. Kedalaman lubang kira - kira sekitar 8 cm, atau kira - kira sampai ke tengah dalam mesin. Jadi ketika Anda memasukkan tongkat media pembersihnya, bisa dikira - kira seberapa dalam nantinya sampai saat Anda selesai membersihkan lubang.
Baiknya lubang ini selalu diperiksa secara berkala, terutama untuk motor yang sering melewati jalan basah, jalan berlumpur (becek) atau sering terkena hujan.
Thursday, February 14, 2008
The Opening
Puji syukur Alhamdulillah dengan mengucap Bismillah blog saya yang ber-title SCHAB's Blog ini sudah online dan dapat diakses oleh khalayak ramai.
Blog ini dibuat sebagai sarana menampung tulisan pribadi ataupun saduran yang diambil dari sumber luar yang terpercaya dengan atau tanpa editing oleh penulis blog ini. Menyadari akan adanya kebutuhan informasi dari banyak kalangan yang berbeda termasuk saya sendiri, semoga blog ini dapat memenuhi sebagian dari kebutuhan tersebut.
Silahkan berkomentar pada section komentar pada masing posting di blog ini sebagai saran, masukan dan kritikan atau mungkin pujian.
Salam & terima kasih.
-AdeShabri-
Blog ini dibuat sebagai sarana menampung tulisan pribadi ataupun saduran yang diambil dari sumber luar yang terpercaya dengan atau tanpa editing oleh penulis blog ini. Menyadari akan adanya kebutuhan informasi dari banyak kalangan yang berbeda termasuk saya sendiri, semoga blog ini dapat memenuhi sebagian dari kebutuhan tersebut.
Silahkan berkomentar pada section komentar pada masing posting di blog ini sebagai saran, masukan dan kritikan atau mungkin pujian.
Salam & terima kasih.
-AdeShabri-
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