Full Backup Removes all Previous Differential eta

[therzog]

My backup is configured to run FULL, Diff, Diff, Diff, Diff, Diff then another FULL., and retain (2) FULL backups. So after 2 full cycles, I should always have my Live data plus (2) Full backups.

E.g.: Dynamics --> Full Copies=2 Diffeential Copies=5

When the 2nd FULL backup runs, it deletes ALL DIFF backups between the FULL backups. So after the 2nd FULL, my sets look like: FULL (5 days ago), FULL (last night).

Is this the intended behavior?

If so, what should happen is to delete DIFF sets 1-4, retaining the last DIFF. That way Diff(5)+FULL(Previous) at least gives me a 2nd full set that is no more than 4 days old.

Or, the other option is to not touch the DIFF sets and retain them based on the "Differential Copies to Keep" setting.

[cobian]

Yes, a differential backup is meaningless without the original full backup, so if a full backup is deleted, all its differential or incremental backups are also deleted.

[therzog]

It left the original FULL (now minus all its Diff's).
I do not know if this is an artifact for my initial setup/testing, but what should be there after the completion of the 2nd FULL? i.e. (2) FULL + (5) DIFF?

[cobian]

Perhaps the first full backup was parked?

[therzog]

I will keep an eye on it through the next FUll cycle and see what happens.