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Gzip is the most popular and effective compression method. Most modern web browser supports and accepts compressed data transfer. By gziping response time can reduced by 60-70% as compare to normal web page. The end result is faster web site experience for both dial up (they're not dead yet - I've dial up account for backup purpose) and boradband user

This document describes how to get the NetGear WG311 wireless PCI card to work under Ubuntu Linux using Ndiswrapper and wpasupplicant software with WPA / WPA2 encryption.

Linux comes with many serial text and gui based serial communication programs. My favorite is minicom - friendly menu driven serial communication program. If you are addicted to DOS / Windows TELIX (a telecommunications program originally written for DOS and was released in 1986), minicom is for you under Linux / UNIX. Let us see how to configure minicom for my Soekris net4801 Single Board Computer / embedded Linux device.

I’d like to configure my Debian box to backup two remote servers using rsnapshot software. It should make incremental snapshots of local and remote filesystems for any number of machines on 2nd hard disk located at /disk1 ( /dev/sdb2). How do I make backups?

rsnapshot saves much more disk space than you might imagine. The amount of space required is roughly the size of one full backup, plus a copy of each additional file that is changed. rsnapshot makes extensive use of hard links, so if the file doesn’t change, the next snapshot is simply a hard link to the exact same file.

How do I improve my file server performance. I've many large files in directories and how do I speed up access time? The -D option causes e2fsck to try to optimize all directories, either by reindexing them if the filesystem supports directory indexing, or by sorting and compressing directories for smaller directories.

One of my responsibilities is backing up UNIX server. HP-UX offers various commands just like any other UNIX system to backup file system, data and applications. How do I backup data under HP-UX UNIX? How do I use mt, fbackup and frecover commands to perform full and incremental backups?

A rootkit is a program designed to take fundamental control of a computer system, without authorization by the system’s owners and legitimate managers.

Most rootkits use the power of the kernel to hide themselves, they are only visible from within the kernel. How do I detect rootkits under CentOS or Debian Linux server?

biosdecode is a command line utility to parses the BIOS memory and prints information about all structures (or entry points) it knows of. The DMI table doesn’t only describe what the system is currently made of, it also can report the possible evolutions such as the fastest supported CPU or the maximal amount of memory supported. In this tip you will learn about decoding BIOS data (dumping a computer’s DMI ) and getting all information about computer hardware without rebooting the server.

FTP is insecure protocol, but file-transfer is required all time. You can use OpenSSH Server to transfer file using SCP and SFTP (secure ftp) without setting up an FTP server. However, this feature also grants ssh shell access to a user.

In this article series we will help you provide secure restricted file-transfer services to your users without resorting to FTP. It also covers chroot jail setup instructions to lock down users to their own home directories (allow users to transfer files but not browse the entire Linux / UNIX file system of the server) as well as per user configurations.

By hiding out DNS server version number you can improve server security. fpdns is a program that remotely determines DNS server versions. It does this by sending a series of borderline DNS queries which are compared against a table of responses and server versions. (just like nmap command's remote OS detection facility).

A nameserver basically responds to a query. Interoperability is an obvious requirement here. The standard protocol behavior of different DNS implementations is expected to be the same.