Verifcation and Restore is failing

[staypo]

Hi,

I'm completely new to this topic and in general i've no idea what am i doing.
I have a PVE 9.1.19 running and a deticated Pi5 with PBS 4.2.0.
I installed PBS via this https://github.com/dexogen/pipbs

On top I have a Synology and attached it via iSCASI to the PBS via this https://www.derekseaman.com/2025/08...-lun-for-proxmox-backup-server-datastore.html

I was able to successfully create backup of my VM/PBX etc, but I'm not able to verify/ restore them.

ProxmoxBackup Server 4.2.0
Namespace:
Root
Search
group, date or owner
()
2026-05-23T10:25:24+02:00: verify synology:vm/102/2026-05-22T07:59:51Z
2026-05-23T10:25:24+02:00: check qemu-server.conf.blob
2026-05-23T10:25:24+02:00: check drive-scsi0.img.fidx
2026-05-23T10:25:24+02:00: verify synology:vm/102/2026-05-22T07:59:51Z/drive-scsi0.img.fidx failed: Unable to open fixed index "/mnt/synology/vm/102/2026-05-22T07:59:51Z/drive-scsi0.img.fidx" - EINVAL: Invalid argument
2026-05-23T10:25:24+02:00: check drive-efidisk0.img.fidx
2026-05-23T10:25:24+02:00: verify synology:vm/102/2026-05-22T07:59:51Z/drive-efidisk0.img.fidx failed: Unable to open fixed index "/mnt/synology/vm/102/2026-05-22T07:59:51Z/drive-efidisk0.img.fidx" - EINVAL: Invalid argument
2026-05-23T10:25:24+02:00: verify synology:vm/102/2026-05-22T07:59:51Z - manifest update error: mkstemp "/mnt/synology/vm/102/2026-05-22T07:59:51Z/index.json.tmp_XXXXXX" failed: EACCES: Permission denied
2026-05-23T10:25:24+02:00: Failed to verify the following snapshots/groups:
2026-05-23T10:25:24+02:00: vm/102/2026-05-22T07:59:51Z
2026-05-23T10:25:24+02:00: TASK ERROR: verification failed - please check the log for details

I can see that the mnt has permission set to backup:backup but I never created this user. I changed it to root:root but still cant work with it.

I happy to provide any logs.

Can someone please help me.