A typical CentOS 7 Linux system has multiple kernels. How many kernels you have in your CentOS systems depends on the configuration setting. Sometimes you might feel the need to change the default kernel to a different one (it may be an older or newer kernel) to ensure a particular Read More
How to Check Yum History in Red Hat or CentOS

One of the most frequently used commands by Linux administrators of a Red Hat or CentOS system is the yum package management tool. Yum History – What For? Some would argue that Yum is the most powerful tool in a Linux systems administrator’s command line arsenal. So what does yum Read More
Get Rid of Old Kernels in CentOS 7 and Red Hat 7

If you’ve been using a CentOS 7 or RedHat 7 system for some time and updating it regularly, you’re bound to accumulate multiple kernels. In this post, we’ll learn how to check the number of installed kernels on a CentOS, RedHat or Fedora box and remove the older ones. Check Read More
How to Set Up Password Aging on CentOS 7

In this age of relentless online attacks by criminals, forcing password changes upon users is a must adopt security policy. As any seasoned Linux system administrator will tell you, only idiots don’t implement password aging. The concept of setting timelines for password validity is known as password aging. The key Read More
Check Version of CentOS

CentOS (the unsupported, free version of Red Hat Enterprise Linux) is considered one of the most robust Linux distributions around. Countless medium and large businesses and, increasingly lately, Linux enthusiasts run CentOS. So it’s worthwhile to understand how to determine the version of CentOS running on your server or desktop Read More
How to Find Version of Packages on CentOS

Every now and then, there arises the necessity for Linux administrators to find out what version of a particular package is running on a CentOS, RedHat or Fedora system. As is to be expected, the commands to find out which version of a package is installed on RedHat, CentOS and Read More