So this is the reality and it just so much confirms all my reasons to leave. I started 15 years ago as a software developer but got into Linux admin stuff. I enjoy both but everything just moved to me being admin all the time. I set up Promxox clusters, site to site VPNs and Puppet, all just because noone else did it. Everything works fine, we have backups (and can restore them) for about 1 year, daily full and for important data more often than daily.

But whenever I started to ask for relief, someone else working with me on admin stuff, more time or project planning for admin stuff, nothing came from management. I took on Windows admin of our Server 2012R2 infrastructure even though I hate it. I asked that we employ someone who knows sysadmin stuff to account for the workload and the bus factor, no response. instead, they hired a software developer even though I said I wanted to get back into SW development.

Anyway, I put in my resignation and they were shocked. I had my last day last week and honestly, I don't see a bright future for the company. My boss tried for the last month to move our 120 VMs from the fully working Proxmox Ceph stack to Windows Server (something with Azure HCI I think) but made little to no progress. (He started this because he "knows Windows better than Linux".) He inquired about an alternative backup solution (I used bup for efficient backups) with a vendor and was a bit surprised by the pricing (oh, really?).

They asked me to do (paid) chat support for them after I leave and I agreed, but I think I won't do this for long. I think I mostly agreed to see what kind of issues they would run into.

TLDR: Leaving my company as the only Sysadmin and noone takes over from me, leaving them completely clueless.