Video Screencast Help

Backup to Disk, then duplicate/move to tape when expired

Created: 04 Jan 2013 | 13 comments

I'm hoping I'm missing something, but I haven't been able to find a way to do this.

The plan is to retain 3 months of backups on Disk, and any copies outside of that live on tape. In practice this means our "weekly" (1 month retention) and "monthly" (3 month retention) backups live on disk only,  since they expire within that time. However, "quarterly" (1 year retention) and "yearly" (infinite retention) live on disk for 3 months, after which they only exist on tape.

I've been using SLPs, but it occurred to me that for the first 3 months, I end up with copies on disk as well as tape. This is unnecessary and unwanted, and the space on disk/tape does add up when one considers our whole environment.

Is there a way for a given backup to live on disk, then duplicate (if necessary) to tape once the disk copy expires?

Comments 13 CommentsJump to latest comment

RamNagalla's picture

Is there a way for a given backup to live on disk, then duplicate (if necessary) to tape once the disk copy expires?

you will never able to duplicate the data once the disk copy expires, after expering there will no source to duplicate it.

you just need to plan Retenction of the images on each destination (disk and tape) and desing the SLP according to that..

my understand is that you would like to keep the quaterly and yearly backup only on tape.

for quarterly" and yearly backups , create a SLP policy such a  way that.. the backup retenction is for 3 Months.and Duplicate to tape with your desired Retenction.

with the SLP as your are sying you are seeing the images on disk and tape, there may be a possiblity of misconfiguration or all the images are not duplicated.

1) check your rentection for Disk

2)make sure you have all the images are duplicated to tape

use below command to see the backlog of duplicate images.

/usr/openv/netbackup/bin/admincmd/nbstlutil report

hope this helps.

Marianne's picture

Once disk copy has expired, there is NOTHING left to duplicate! Disk copy gets deleted when it expires.

Have another look at SLP's with different retentions for backup copy on disk an duplicate copy on tape. 

Create different SLP's for quarterly and yearly schedules.
Backup your daily, weekly and monthly directly to disk, no SLP. 
Use STU override in schedule to select SLPs for quaterly and yearly backups.

I would personally prefer to have monthly backups on tapes as well... Seen to many times users asking for a restore from a specific monthly backup...

Supporting Storage Foundation and VCS on Unix and Windows as well as NetBackup on Unix and Windows
Handy NBU Links

smckelvey's picture

I think you've misunderstood my question, or I've done a poor job of phrasing it.

I understand that I can't duplicate an "expired" image.

I also understand that I can set different retention times using the SLPs, and that is what I am doing. It works just fine. For example, I run a quarterly backup:

  1. backup primary copy to Disk with a 3 month retention since that's the max we are allowing on disk.
  2. very soon after, SLP duplicates it to tape with a 1 year retention since that is how long we actually want the data to be available.

So now I have one copy on disk and one on tape at the same time for the first 3 months. Perhaps not that big a deal, but like I said, when I add up everything in our environment, it makes a difference and that's a business expense that there's no reason to incur in my opinion.

Alternatively, I'd like to be able to:

  1. backup to disk w/ a 3 month retention
  2. but not duplicate to tape until the copy on disk will expire.

Hopefully that makes sense. I see there's a setting in SLP to expire once duplicated, but that doesn't seem to help since I can't control when duplication happens.

RamNagalla's picture

If i understand you correctly, you just need the duplication to happen just before the image expires.

you can do this with Vault,and scripts. but its little bit risk..

the major question is: - what if the Duplication job failed(did not noticed before the expire date) and you are ended up with Expiring the image?

even with the Vault you still can achive it with below apporach.

lets say..

Keep your Primary disk copy retenction as Infinity.

configure your vault to choose images for backup older then 80 or 90 days.( in the vault choose backups tabe ..between 100 to 80 days something like that)

select the option in vault duplication tab, that expire original disk backup image after XXX hours.

and check how it work for you.. 

you can achive the same with scripts.

Hope this helps.

Marianne's picture

If you read through your opening post again, you will understand why Nagalla and I both misunderstood... wink

You are right - SLPs cannot be scheduled or controlled. It is designed to run duplication as soon as possible after the backup. Future NBU releases will probably have SLP scheduling feature.

I don't understand what cost difference it makes whether your duplications run now or in 3 month's time. With Infinite retention period, you are in any case going to run out of tapes sooner or later... Quarterlies need to be kept on tape for a year, whether it gets done today or in 3 months time...

Let data protection be your first priority, not short-term cost saving.

Supporting Storage Foundation and VCS on Unix and Windows as well as NetBackup on Unix and Windows
Handy NBU Links

smckelvey's picture

Not really, but that doesn't matter.

So, the answer to my question is that there's no way to do what I'm looking to do(we are not licensed for Vault)? I was wondering if there might be some mechanism or setting of which I wasn't aware.

While not germain to my question, costs vary and are relative, but the bottom line is it's duplicative effort and resources, and there's no need for it. I fail to see how wanting to duplicate later rather than sooner can be perceived as not making data protection a priority. And you think it is because we want 1 copy instead of 2,  then why not have 3 copies or even 10, just to be safe........

RamNagalla's picture

Let data protection be your first priority, not short-term cost saving.

it should be our top Priority.. agreed with Marianne

Nicolai's picture

NBU 7.6 will have the option to duplicate a image at creating time (the way it works today) or when the image reaches end of life.

Assumption is the mother of all mess ups.

If this post answered your'e qustion -  Please mark as a soloution.

RamNagalla's picture

If Vault is Not licensed , you can achive the same with the scripts,

keep the Primary disk copy retenction as Infinity.

create a scipt in such a way that, it will look for the images older than 80 days, and check if those images have the copy 2 or not.

if those images does not have the copy 2 it will run the duplicate command againist those Images ,

and if the script finds the copy 2 on tape , then it will run the expire command on copy 1(disk copy)

this is the only other option I am seeing to achive your requirement.

Hope this helps.

Jim-90's picture

Probably cheaper to let NBU to handle everything automatically through SLPs rather than use NBU Vault.  Tapes are a lot cheaper than than the admin staff costs of using vault.  

The only time I would use vault is when you have to delay the duplication for some reason (usually resource allocation).

Mark_Solutions's picture

I support of the other excellent replies please consider this ...

Today you backup to disk with a 3 months retention and plan to duplicate it to tape in 2 months and 28 days time.

In 2 months and 27 days time you data center is flooded

You now have no data!

OR ..

You backup and duplicate today and get those tapes off site - now you are safe!

I would look again at your SLPs - you could always have a shorter retention on disk if you wish - everything stays on disk for 2 months (or less for incremental backups) but tapes have the desired retention period.

This gives you a nice set of disk images for quick restores but also gives you everything safely off site to be prepared for a disaster

Always send your catalog backups off site too if possible - DR planning is as important as the backups themselves as without a DR plan your backups may not be worth anything.

Hope this gives some food for thought

Authorised Symantec Consultant . Expert Partner.

Don't forget to "Mark as Solution" if someones advice has solved your issue - and please bring back the Thumbs Up!!.

smckelvey's picture


Appreciate the food for thought, but we are doing offsite tapes separately and doesn't really apply to this discussion.

My question is strictly about creating/maintaining onsite tape copies for backups that have a longer retention that what we have on disk.


Appreciate the feedback. Scripting, while possible, seems too labor intensive and prone to problems.

We don't have vault, nor do I see us purchasing it.

SLPs are working pretty well for us, I just didn't like the fact that I had to write a tape and disk copy at the time for anything we wanted planned on keeping past the 3mo retention on disk.

I'll look forward to 7.6 though, and see what other options are available.

Nicolai's picture

Thanks for the feedback.

Please consider marking one of the post as a solution. By marking as a solution you can give a free tip to one of the contributors.

Best Regards


Assumption is the mother of all mess ups.

If this post answered your'e qustion -  Please mark as a soloution.