Eric Peterson wrote: > yum grabs the variable 'distroverpkg' from /etc/yum.conf. Thanks Eric. I see that variable on a Red Hat 9 system. Unfortunately, 'distroverpkg' does not appear in /etc/yum.conf on the Red Hat 7.3 system in question (which I'm beginning to suspect was imperfectly upgraded from 7.2). So I hard-coded a '7.3' in place of $releasever in /etc/yum.conf and that seems to do the trick: # yum check-update Gathering package information from servers Getting headers from: Red Hat Linux 7.3 base Getting headers from: Fedora Legacy utilities for Red Hat Linux 7.3 Getting headers from: Red Hat Linux 7.3 updates Finding updated packages Downloading needed headers <lots-of-stuff ...> Now just I have to decide if I should risk breaking things.