Media Protection - Overwrite and Append FAQ

[andymcp]

Does anyone have a difinative FAQ or document on Overwriting and appending media. I have looked at the vertias admin guide and it just blows my mind.

I am trying to work out my rotation for work.

I have a three week rotation on a 7 tape cartridge (autoloader).
I do a full backup on a friday night (188 gig) then monday to Thursday I do a Differencial which is about 5-13 gig per night.
And then change the cartridge on friday morning

Do I set the allow append for 1 week and the overwrite for 2 week or what? This is the bit I am not to sure about.

many thanks

Andy

 

[steveot]

Overwrite period for 3 week and append it shouldnt matter. Just leave it as infinite allow append.

OVerwrite means we protect the tape from being overwritten for x amoung of time.
Append period means we can only add to a tape for x ammoung of time.


The basics of Advanced Device and Media Management for VERITAS Backup Exec (tm) for Windows Servers

http://seer.support.veritas.com/docs/192265.htm

An explanation of the "Overwrite Protection Period" and the "Append Period"

http://seer.support.veritas.com/docs/237374.htm

 

[andymcp]

yes I initially thought that is should be three weeks but veritas states that it is from the end of the backup job. Would the backup job be once when the full backup finished and when each of the diff backups finished as well. Which if we have a surge in data on the servers some of the tapes will not be available due to the overwrite period not running out. If we specify two weeks the whole of the cartrige will be available for backups.

Is that right.

Andy

 

[steveot]

Right. I would go with two week as you suggest or 15 day, etc. That will ensure that if you backup runs past the normail time the tapes will be expired and ready to be overwritten in the next cycle.