NBU 7.5 - What happens to archive bit when you cancel a diff?

[nbu_scott]

Hi all- To be more specific, I'm curious about how the archiving bit works in this scenario. If you cancel a diff, it doesn't appear that the partial backup is usable for restore purposes. I was also under the assumption NBU would clear the archive bit as files are processed. Putting thse two together, it would seem like files processed before a backup is cancelled have their archive bit incorrectly non-set - is that how it works or am I missing something, because that's certainly not desirable.

All this is based on the assumption NBU uses the archive bit.

Thank you!

Scott

[Marianne]

Archive bit is cleared after successful backup.

The 'Wait time before clearing archive bit' in Windows Client properties is 300 (5 min).

Extract from Admin Guide I:

Wait time before clearing archive bit: 
Specifies how long the client waits before the archive bits for a differential

incremental backup are cleared. The minimum allowable value is 300 (default).

The client waits for acknowledgment from the server that the backup was

successful. If the server does not reply within this time period, the archive bits

are not cleared.

This option applies only to differential-incremental backups.

Cumulative-incremental backups do not clear the archive bit.

[nbu_scott]

Thank you for the very quick reply, Marianne! That gives rise to one more question though - is it possible for a file to be archived, then modified (while the backup is still running), then the post-backup archive-bit clearing job incorrectly clears the flag since the file was modified after it was archived by NBU?

[Marianne]

Hi Scott

I have in all honesty never tested your theory in real life.

It should be easy enough for you to copy some files to temp folder, create test policy and perform tests as per your post? I am quite curious to know the result...

You also have the option to de-select 'Incrementals based on archive bit'. 

This will perform Incr backups based on file datestamp.

As per the manual:

Disable this property to include a file in an incremental backup only if the date

and time stamp for the file has changed since the last backup. For a

differential-incremental backup, NetBackup compares the date/time stamp to

the last full or incremental backup. For a cumulative-incremental backup,

NetBackup compares the timestamp to the last full backup.