[CentOS-mirror] Stale mirror content

Hello,

I'm seeing issues with stale content from mirrors that are listed as being up to date at https://mirror-status.centos.org/

For example the repomd.xml file at http://mirror.it.ubc.ca/centos/7/updates/x86_64/repodata/ has not been updated since June 25, but the current file on other mirrors was updated July 16. This is not the only mirror with this problem.

I use the default mirror pool, rather than specifying a specific mirror. I became aware of this issue because I've lately been receiving dozens of messages like these everyday.

/etc/cron.hourly/0yum-hourly.cron:

Not using downloaded extras/repomd.xml because it is older than what we have: Current : Mon Jul 6 08:06:49 2020 Downloaded: Wed May 20 13:19:30 2020