Centos / Redhat Remove old kernel versions

Hello again

So today I started installing a few updates on one of my servers (centos 7) and had the following issue , I could not install the new kernel version because there was not enough disk space in /boot to accommodate the new kernel , so I went about removing the old files, and solving this problem permanently , so first I installed yum-utils

#yum install yum-utils

Then I used the package-cleanup utility (handy python script , yay python!!! )  that allows us to remove duplicate or orphaned packages.

Here is an example

#package-cleanup –oldkernels –count=2

so what this does is that it removes old kernels and keeps only the last 2 .

So this does what we want , which is to remove the older version of the kernel , however we might have this problem again in the future . Looking for a solution I have checked /etc/yum.conf and there we have the option


according to Red Hat and their deployment guide present here


…where value is an integer representing the maximum number of versions that can be installed simultaneously for any single package listed in the installonlypkgs directive.
The defaults for the installonlypkgs directive include several different kernel packages, so be aware that changing the value of installonly_limit will also affect the maximum number of installed versions of any single kernel package. The default value listed in /etc/yum.conf is installonly_limit=3, and it is not recommended to decrease this value, particularly below 2.


So , I changed the yum.conf to read


There , we have avoided this problem.

Of course that this has an impact on how many old versions of the kernel you wish to keep , and I do recommend that you set this value taking into account your needs … but for me at this point I feel that 2 is enough .





Linux Academy … learning further and personal development

Hello all

As we all know a part of being a good Sysadmin is learning hot to reinvent yourself every once in a while. This can happen actually quite often as the tech market moves at lightning speed.  So this week I have started using Linux Academy to improve my Linux Mojo and learn a few new tricks  this is proving to be quite interesting as the website not only provides videos with the training materials but also provides you with labs , actual servers where you can test and learn further, I will document my progress as I go but so far it looks grand !!!

Beware that this is not free it costs around 25$/month but it’s in my opinion it’s well worth it if you can get well prepared for your certifications and learn new things .