[Triumf-linux-managers] CentOS-7.7 on TRIUMF mirror

[Kel Raywood]

This announcement is for those that manage CentOS-7 installations.

CentOS-7.7 was released on September 17 but we left CentOS-7.6 as the 
default on the TRIUMF mirror until we'd run some update tests. Today, 
September 24,  we made 7.7 the default version of CentOS-7 on the TRIUMF 
mirror.

If you installed CentOS-7 using a TRIUMF kickstart, or if you modified a 
standard CentOS-7 installation to use the TRIUMF mirror, then your 
machine will now receive the CentOS-7.7 packages on your next update.   
The TRIUMF-kickstart default is that yum-cron will apply updates when 
daily cron-jobs are run.  This is not the default on a standard 
installation and some groups, especially those that manage servers or 
data-acquisition machines, do not allow auto-updates.

If you use a standard CentOS-7 installation then,  updates have been 
available for a week and your installation may already be up-to-date.

If you expect your machine(s) to be up-to-date, then we suggest that you 
check because there are some things that can go wrong with an 
auto-update.  The most common is that occurs when packages from a 
third-party repo require other packages that lead to a dependency 
conflict when the base is updated.   The wine-* packages in EPEL have 
this issue.   The TRIUMF kickstart installs many packages from EPEL, but 
none that lead to a dependency problem.

*Check if your machine has updated to CentOS-7.7*

     cat /etc/redhat-release

The expected output for 7.7 is: CentOS Linux release 7.7.1908 (Core)

     yum check-update

If you have updated, you will see no or a few packages depending on when 
an update last run.  If you see many packages, including 
centos-release-7-7.1908.0.el7.centos, then your CentOS-7.7 installation 
is not up-to-date.   Run the update manually (yum update) to see where 
it fails.

*Removing packages that cause a dependency problem*

Having identified packages that cause a dependency problem, it is 
usually straight-forward to remove them, updated and then reinstall.  
e.g. if you have wine packages installed do:

     yum remove --remove-leaves wine
     yum update
     yum install wine

*If possible, reboot after updating*

It's good to reboot after updating to ensure that there aren't any 
problems; especially with video configuration.

--
Kel Raywood
TRIUMF Information Systems & Technology