Comparing Installed vs Update Package Versions on CentOS 7 & 8

Submitted by kevin on Wed, 03/10/2021 - 21:20

When updating CentOS it can be very useful as a sysadmin to compare the incoming update package versions against the currently installed version. However this isn't an overly easy task as the installed version numbers are not printed out in the resulting dnf/yum update summary table.

Updates coming in can be seen in the summary table by running 

dnf update

However a safer command (as you have to rememeber to cancel the command) is:

CentOS 7 Xen PV guests failing to boot with kernel 3.10.0-693.17.1.el7

Submitted by kevin on Mon, 02/12/2018 - 20:57

After updating one of my VPS's I experienced the adrenaline rush of rebooting, waiting, panicking and rolling back a kernel update. Normally updates on CentOS are stable and nothing to worry about. However after all the fast patches to the kernel due to the new Intel/CPU based vulnerabilities I was rightly cautious to run the updates on a non-vital server first.

Kernel Update 3.10.0-693.17.1.el7 was the culprit, and as of today (2018-02-12) the CentOS repos including Plus still haven't pushed a fixed version.

Fixing CentOS Yum Diff Warnings

Submitted by kevin on Mon, 12/19/2016 - 13:16

Having been a linux system administrator for quite some time, one of the main annoyances has been fixing changed files when the package maintainers have also added to them. Mostly this can be avoided by using the package.d/custom.conf settings files, however sometimes we are forced to make changes to the core package files.

On the last update the following conflicts came up on one of our systems: