OpenBSD

BASH for loop works nicely under UNIX / Linux / Windows and OS X while working on set of files. However, if you try to process a for loop on file name with spaces in them you are going to have some problem. for loop uses $IFS variable to determine what the field separators are. By default $IFS is set to the space character. There are multiple solutions to this problem.

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Linux and other Unix-like operating systems use the term “swap” to describe both the act of moving memory pages between RAM and disk, and the region of a disk the pages are stored on. It is common to use a whole partition of a hard disk for swapping. However, with the 2.6 Linux kernel, swap files are just as fast as swap partitions. Now, many admins (both Windows and Linux/UNIX) follow an old rule of thumb that your swap partition should be twice the size of your main system RAM. Let us say I’ve 32GB RAM, should I set swap space to 64 GB? Is 64 GB of swap space really required? How big should your Linux / UNIX swap space be?

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Cheat sheet act as a reference tool which provides cut and paste kind of commands to complete a specific task. I often recommend following set of best cheat sheets to students and IT professionals. It include Linux / UNIX command and shell scripting.

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OpenBSD 4.4 has been released and available for download (jump to download link ) from official project website. OpenBSD is often the first to add new security tools to make it harder to break, developers have also carefully read through the programming code to check for mistakes more than once.

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A Redundant Array of Independent Drives (or Disks), also known as Redundant Array of Inexpensive Drives (or Disks) (RAID) is an term for data storage schemes that divide and/or replicate data among multiple hard drives. RAID can be designed to provide increased data reliability or increased I/O performance, though one goal may compromise the other. There are 10 RAID level. But which one is recommended for data safety and performance considering that hard drives are commodity priced?

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PuTTY is a terminal emulator application which can act as a client for the SSH, Telnet, rlogin, and raw TCP computing protocols. You can use putty for remote login or to control your router connected via serial devices.

By default PuTTY stores the session information in the registry on Windows machine. If you have several PuTTY sessions stored in one laptop and would like to transfer those sessions to another laptop, you need to transfer HKEY_CURRENT_USER\Software\SimonTatham registry key and value as explained below.

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