Been there, it’s not fun. Transitioned the new HPC cluster from redhat to suse. Switched to Centos after a few years on suse due to pricing and their software becoming more and more unstable. The following cluster got CentOS from the start and then got migrated to rocky after they switched Centos to rolling release. It’s not easy running this stuff…
Nah, prices have gone up considerably. Generally around 250~350€ per year per Server depending on your deal for Redhat. SUSE is about the same, both are currently recalculating, most likely upping the price. HPC-nodes cost less (somewhere around 30-80€/year). But they make it all way too complicated by binding license costs to CPU count for example and now after abandoning that to other nonsense. Lead to a brief popularity of dual-core servers a few years ago, since Oracle licenses were all CPU-core count based. Don’t know how that is currently going.
Also it depends on other stuff like support levels and whatnot. We once had to get an expert on licensing costs to get an offer for licensing a few servers and even these people could not respond immediately and had to go through several documents to calculate the price - note those weren’t resellers, those were from the Company themselves. I had to stiffle a few laughes during that conference…