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mkisofs: Repackaging a Linux Install ISO

In the office I use Red Hat quite often and one of the quicker ways to provision a Red Hat server is via kickstart. There are many ways to reach a kickstart file during initial install (NFS, HTTP, FTP) but one of the ways I commonly use is to put the file on the installation DVD itself. The below steps are what I use to add a custom directory to the installation iso file.

ssh-keygen: Creating SSH Private/Public Keys

Are you tired of trying to memorize tons of passwords on different systems? Or do you simply want to have a faceless user SSH between two systems without being asked for a password? Well you are in luck because today we will be covering SSH keys. SSH Servers have the ability to authenticate users using public/private keys. In the case of pass-phrase less keys this allows users to ssh from one system to another without typing a password.

Packing and Unpacking files with GNU Tar

One of the most basic tasks for any Sysadmin is packing and unpacking files for various reasons. While there are many ways to perform this task GNU Tar is probably one of the most recognized and commonly used tools by Linux/Unix users. A little history on tar The tar command is a command that appeared in the early days of Unix and has had several changes made over time. Originally the command was used to take files, combine them into one file and write them to a tape archive (tar).

NFS: Setting up a basic NFS file system share

While there are many distributed file systems out there; especially with the rise of cloud & virtual computing. The Network File System or NFS protocol has by far held its title as an easy to use, fast to implement and very efficient distributed file system. In today's article I will be covering how to set up a basic NFS share. This article will assume that you have already created a file system, if not hop over to this article and then come back for the NFS steps.

Cheat Sheet: Cutting Text with cut

The cut command is a Unix/Linux tool used to literally cut text from files and output from other commands. With the cut command a user can take text and output only certain parts of the line. In my opinion cut is the most under recognized and utilized command in Linux/Unix. This is mostly due to the fact that when most Sysadmins want to cut text from files or standard output many will reach for AWK.

iptables: Linux firewall rules for a basic Web Server

For today's article I am going to explain how to create a basic firewall allow and deny filter list using the iptables package. We will be focused on creating a filtering rule-set for a basic everyday Linux web server running Web, FTP, SSH, MySQL, and DNS services. Before we begin lets get an understanding of iptables and firewall filtering in general. What is iptables? iptables is a package and kernel module for Linux that uses the netfilter hooks within the Linux kernel to provide filtering, network address translation, and packet mangling.