Red Hat Enterprise Linux

That is the certificate I earned upon completing community college. Their Linux curriculum was originally designed around Debian, but when IBM acquired RHEL, redesigned to offer this foot-in-the-door.

IBM still seems to do alright in the legacy mainframe/mini market. It is quite strange how the AS/400 and zOS stuff all goes without notice of ordinary IT guys like me, as if it didn't exist, but still powers a lot of machine rooms that aren't AI data centers.

System z machines come with special AI processor modules these days, so it's clear IBM wants a piece of that pie also.