Netbackup Retention Policy

[AROOKIE]

I'm new to Netbackup and I have a few questions about Retention policies. I have an Quantum ATLP7000 with 16 Drives Connected to 3 Media Servers and one Master/Media Server. I'm Using Netbackup 4.5 (MP5). There are about 300 SDLT3 Tapes in the Backup Device and right now the retention Policy on all Full and Cumulative-Incremental backups is set to 3 Months.

a) How do I know when Netbackup needs more tapes for this level of retention policy? Is it going to tell me that the jobs cannot run until there is Blank Media Available?

b) I have setup the catalogs to be backedup in 2 SDLT 3 tapes. What happens if I have a tape that I need to restore but I dont have the proper Catalog? Can the tape be Cataloged and if so, how?

c) what are the best Practices for setting up retention policices?. With Backup Exec, I used to remove the tapes from the Device after the weekly Full backups were complete, I would then Use the same label to put in a new tape and I would mark what was removed with the proper label number. When I wanted to do a restore and it asked for tape number BSO225S, I would search for that tape and use that lable to restore the data. I understand that this is not recomended and I should never use the same label for multiple jobs. What do you guys suggest?

Thanks

 

[comtec17]

You will need to do some math. If you are saving tapes for 3 months then you will need to find out how much you are backing up during your incrementals and fulls. Then by how many clients and drives.

For example, I have 20 servers all with the same retention that backup 20gb in incrementals daily and 1TB in data during the fulls. Because you are using 16 drives you are at least using 16 tapes for your fulls and 16 for your incrementals. I would say with this scenario that I am at least using 40 tapes per week x 12 weeks = 480 tapes for 3 months.

I would suggest you use the Vaulting feature of NBU 4.5 and offsite your catalog for 3 days. I would also suggest you use Vaulting for your Full Backups. You could either duplicate or send originals offsite. This will keep your library from running out of media.

 

[Tommojunior]

Hi,

Don't forget that you can make use of the "scratch pool". This is a pool of tapes, which are held in reserve (so to speak) for when any other "real" pool runs out of tapes.

Any new tapes you get in get added to the scratch pool. There may be some basic maths to do still, but all you have to do is count the net loss of tapes you send off site each day (you do send off site don't you!) and buy some replacements. Net loss - Because I guess that like everyone else you have an organic growth of data, which can be increased further depending on your retention policies:

We use incs each day but Saturday, when we run a full. We also run a special full on the last saturday of each month which has a longer retention period. The retention periods of both our incs and regular fulls is the same (say X days).

When X days is up, those tapes get returned to site from off-site storage. The special "last saturday fulls" have a retention period of Y years. Because we've been using netbackup for less than Y years, the number of tapes with this retention level increases on the last saturday.

Get it? ;-)

Oh - and use Vault, it does exactly what it says on the tin (and more)