After installing an HTTPS certificate, the following problem started occurring:
2024-05-19T08:41:52.869412+02:00 server pvestatd[1481]: backup-server1.example.com: error fetching datastores – fingerprint ‘X’ not verified, abort!
2024-05-19T08:41:53.063071+02:00 server pvestatd[1481]: backup-server1.example.com: error fetching datastores – fingerprint ‘X’ not verified, abort!
On this post:
https://forum.proxmox.com/threads/pbs-error-fetching-datastores-fingerprint-xx-not-verified-abort-500.90342/
You do not need a fingerprint if you use ACME, because that generate correctly signed certificates.
Datacenter -> Storage -> Edit Storage
Remove fingerprints on backup storage