yum

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:

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: