One of the first things that should be done after a fresh operating system install is to see what services are running, and remove any unneeded services from the system startup process. You could use a port scanner (such as nmap ) and run it against the host, but if one didn’t come with the [...]

There are many log files in linux systems, but we will outline six that are most important.

/var/log/cups/ - This directory stores the log files for the printing system CUPS.
/var/log/news/ - This Directory stores messages for the news system.
/var/log/boot.msg - When the system boots, all boot script messages are displayed on the first virtual console. This [...]

One of the crucial task one have as an administrator is to make sure that there is no suspicious activity on the system that might compromise security.
Monitoring tasks include evaluating login activity for signs of a security breach, such as multiple failed logins.
To monitor login activity, you can use the following six commands.

who. This command [...]

The following is a list of rules and tips you might find useful in dealing with basic security concerns:

Avoid doing your regular jobs when you are logged in as root. This reduces the risk of getting a cuckoo egg or a virus and protects you from your own mistakes.
If possible, always try to use encrypted [...]