I am new to the proxmox environment and would like to know if it is possible to backup to tape. If so, I would like to know if all tape robots are compatible with proxmox backup.
yes PBS is compatible with Tape drives and libraries. I use it to do regular backups and works just fine.
I think they support most standard LTO tape libraries, although not sure which ones.
we generally support drives >= LTO5 and try to support as many changers as possible. if there is one that makes problems, we'll try to fix support for it
In addition to Dominik's statement ">= LTO5": when I first installed PBS I had no problem at all running my LTO3 drive (Dell branded external SCSI). A while back I switched to SAS attached LTO 4 (also external, HP branded) and continued using the LTO3 media pools just fine.
If you're looking into tape robots, you're probably not confined to end-of-life LTO generations, so I write this just as a data point of no-probleminess