Problems with Allocation Policies

[982134098123]

Hello, so i got the following Allocation Policies for my Media Pools:

And the following Backup-Job:


From time to time i get the Error: "TASK ERROR: alloc writable media in pool 'Weekly' failed: no usable media found"

I have a 4 Set rotation of Tapes. Am i missunderstanding the Allocation entry?
As i understand the Documentation it counts the current set + the Retention time.
I thought it would be usable for the Backup after 4 Weeks, but as my Error obvious not.
If someone could point out my error i would be very grateful.

 

[dcsapak]

hi, sorry for the late answer

From time to time i get the Error: "TASK ERROR: alloc writable media in pool 'Weekly' failed: no usable media found"

when for example did you get that error? on which job? what was the state at that point (if you can remember?)

from the docs (https://pbs.proxmox.com/docs/tape-backup.html#media-pools):

Retention period starts on the creation time of the next media-set or, if that does not exist, when the calendar event next triggers after the current media-set start time.

so a backup started at sat 2:01 + 3 weeks of retention time is sat (3 weeks later) at 2:01, depending on the timing, it may happen that the newly allocated media set is a second or so earlier than it was last time
imho the safe way to do this is to use something like 20 days instead of 3 weeks (so essentially leaving a day of buffer time)