Linux System Administration

Once you have a distribution of the Linux operating system installed, steps must be taken to keep it running smoothly and securely. The purpose of this class is to introduce concepts and tools which can help achieve that goal.

All Linux systems have a command line interface. Some have web servers and/or the X Window system. When there is a problem with the system, the web server and GUI will likely be nonfunctional but the CLI will probably still work. For this and several other reasons we will use the CLI to manage and administer Linux in this class.

The topics relevant to this topic include the following. We will cover as many as reasonably possible in the time available.

• Adding and Managing Users
  • useradd, userdel, usermod
  • Configuring user environments with /etc/bashrc and /etc/skel.
  • Restricting users with quotas
• Installing software
  • RPM files
  • Source Code
  • Automatic Updates with yum
• Managing Server Programs
  • Starting and stopping servers (daemons) with service or SysV scripts.
  • Determining which servers will be started automatically during the boot process with ntsysv and the rc.d run level directories.
• Backup and Recovery with tar
• Security
  • Install only the software which is needed
  • Firewalls--Open only the ports which are needed
  • Configuring with security in mind
  • tripwire--Detect changes in key programs and files
  • chkrootkit--Find evidence of intrusions
  • Use encryption whenever possible--ssh, scp
  • Limit access to the root user account with sudo
• Useful configuration files
• Creating adminstration tools with bash and cron.

Although our courses do not have any required textbooks, some students want to know about the books I have found to be helpful. Here are a few: