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Most efficient way to backup?

Created: 31 Oct 2012 • Updated: 11 Jan 2013 | 6 comments
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I am creating new policies in NetBackup 7.1 to run full backups of 8 x 15TB volumes.  Previously they were set up as 8 policies - 1 for each.  But I've found they can take up to 5 days each to complete.

I have two tape libraries, each containing 8 drives.  Is it most efficient to create policies of smaller parts of each volume, therefore using each of the 16 drives?

I am assuming that each policy (job) will use a seperate drive.  Is this correct?

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Yasuhisa Ishikawa's picture

Do you enabled multistreaming in each policy? If not, NetBackup create only 1 job for each policy. And each job goes active with the drive assigned for it(unless you configure multiplexing). 8 policies will take 8 drives.

In general, it is better to device backup target into smaller piece and run them simultaneously if you have enough resources.

Authorized Symantec Consultant(ASC) Data Protection in Tokyo, Japan

Mark_Solutions's picture

With that size of data your problem could actually be the network?

You have 120TB of data to transfer - if you have a 1gb network (assuming practical rate of 80MB/s) then that would take 436 hours or 18 days

As you have complete it in 5 days i assume you network is teamed or of higher throughput.

The solution here would probably be to have several fibre HBAs in the client and make it a SAN Media Server with direct access to the tape drives

You then need to split each volume into streams and use multiplexing to get the data running to tape in such a way that all streams can run.

Bear in mind that if you use all 16 drives it does not leave any for the rest of your backups so you may just want to use the eight but multilplex with a value of 6 also so that you can run up to 48 jobs at the same time which allows you to split up each policy into 6 streams.

Backing up to disk would also be a great advantage and if you could use de-dupe then the option would be to use the NetBackup Accelerator to reduce backup times

There is a bottleneck in every system be it network, disk I/O, fragmentation etc. - you just need to identify the bottleneck (which will tell you the minimum tome that the backup could be done in) and make sure all other components can manage that speed.

If simply dragging the data from disk is the issue then flashbackup may also assist, though that would mean just the 8 streams as it works per volume and will backups empty space too

Hope this gives you some ideas

Authorised Symantec Consultant

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mph999's picture

It also depends on the layout of the disks holding the data you wish to backup.

It you try and run say 8 backups of different bits of the data, but this is all read of the same one or two physical disks, the performace will drop through the floor.

Proper backup design starts with understanding the individual clients.

Regards,  Martin
Setting Logs in NetBackup:
jonnyguitar's picture

This is great. Thanks for your help everyone.

sazz.'s picture

I guess you are new to Forum, Please mark the post that helped you most, also you can mark you own post as solution if you have done some specific steps that resolved the issue.

This way it can help others directly going to solution and giving some points to the person who helped you.

revarooo's picture

With tha amount of data, you might be better off looking at using deduplication for you backups.

Have you considered PureDisk or adding MSDP storage?