"Henrik Steffen" <steffen@city-map.de> writes:
> while vacuuming I got:
> ERROR: cannot open segment 1 of relation basiseintrag_firma_idx (target block 808923185): No such file or directory
Apparently you have a corrupted link pointer in that index. You can
probably recover by reindexing basiseintrag_firma_idx.
As for how it got that way, would need a lot more info to investigate.
regards, tom lane