Locking Down a Linux box part IV

Today I'm going to go back to the netstat command that I talked about a couple of days ago. Essentially it will show you all the sockets that are in the LISTEN state and the programs that are listening on each port. The big issue here is what services should this particular Linux box be listening for. If this box is being used as a Web server should there be a printer hooked up & should the box be running an lpd daemon in the back ground -- NO!! This is why it is important to only have essential services and daemons running on a Linux box.

There is a good article at the Techrepublic web site titled "Improve your Linux security: Stop unnecessary services". Which talks about the same issues. A sample of the /etc/initd.conf file can be found at the userlocal.com web site.

some other good sites with a good overview of the security implications are found on the Redhat site, YoLinux.com site, and the resnet.ubc.ca site.