How can I restore from copied NDMP-tapes ?

[Jaap_Hartog]

Dear all,

some time ago I was requested to make inbetween backups of some filesystems (on our NAS over NDMP) .
This differed slightly from the way we normally make our NAS-backups in terms of retention and (smaller) size of the backup itself, so it caused no problems.

After having made the first backup, I created a safetycopy and had a look to see if this could be done automatically.
I found out that, contrary to making  Windows-based backups from a SAN, it is not possible to have copies being made parallel to the primary backup as part of the policy. Since it only concerned 3 backups, it is not that much of a problem, so I continued copying manually.

If I now have a look at the BAR-interface (Preview required media ) for restoring one of these backups,
I only see the primary media listed on which the backup was initially made, not the copy.
How can I make sure that, when necessary, I can also restore from the copy-tape(s) ?

Continuing, I also want to make copies of old SAN-backups (MS-Windows based), that are currently on LTO-2 tapes before our environment (NAS+Library with drives) will be upgraded and the drives in the new library are too new/modern to read the LTO-2 tapes.
In fact the same question to end with:
How can I make sure that, when necessary, I can also restore from the copy-tape(s) ?

Thank in advance for your advice !

Kind regards,

Jaap Hartog

[sdo · Accepted solution]

The BAR GUI will only show you primary copy.  Use the Admin Console 'Catalog' function to list other copies.  You can test restore from alternate copies by making an alternate copy the primary copy.  Which then means that a restore will use the alternate copy, which has now been marked as primary, as the copy to restore from.

To make copies of LTO2 to say LTO5/6, then either:

a) Have both tape drive models visible within the same NetBackup domain (they do not have to be on the same master/media or media server)

...or:

b) Duplicate from LTO2 to a holding tank, e.g. DSU, DSSU, Advanced Disk or MSDP; then replace tape drives; then duplicate from holding tank to LTO5/6.

HTH.

[sdo]

You may also want to consider implementing NetBackup KMS tape media encryption, as LTO2 did not support this, but LTO4/5/6 all do.  NetBackup KMS is free, fairly straightforward, and has almost zero (well, about 1%) performance (i.e. slightly longer job elapsed duration) impact on tape read/write - and zero impact on RAM (well, probably a few MB tops - for the KMS daemon) and CPU (again, unnoticeable, just a few cycles for the management processes).

NetBackup did have some restrictions, e.g. I think it was circa 20 encrypted volume pools in earlier versions of NetBackup - but I believe this is now 100 encrypted volume pools in NetBackup v7.6.x.x

Does anyone have the actual maximum numbers of encrypted volume pools for NetBackup KMS for any given NetBackup version?  Or point us to a TN that does?

[Jaap_Hartog]

I had already used the Admin Console 'Catalog' function to list the other copy (I should have mentioned that), but did not know of the option to make alternate primary.
I assume that an RMB on the copy and choosing Set Primary Copy does the trick ?

Our current drives now read LTO-2, write LTO3 and LTO4.
Upgrade is planned not earlier than the end of 2016 (so I still have time)  but I rather have this done too early than too late.
We still have quite a lot of new LTO-4 Tapes, so I am planning to use some of them for the safeguarding of the images that are now on LTO-2, which is not a bad idea anyway because the oldest tapes date from 2005 already.

Thanks for putting me in the right direction !

Jaap

[sdo]

Re: RMB and Set Primary Copy.  Yes, that's how to do it.  FYI, this can also be achieved via the CLI using the 'bpchangeprimary' command.

Are you aware that NDMP backups can usualy/typically only be restored to the same storage platform that they came from?  e.g. It is not generally possible to restore an EMC Celera NDMP backup to a NetApp device - because... NDMP is nothing more that a transport protocol, and not a 'file system'.  NDMP is a carrier stream for embedded propriatery vendor file system formats (usually a form of Unix 'dump' or 'tar' or something very specific to that storage platform).

Also, for example, check whether really old backups from old versions of NetApp can be restored to new versions of NetApp - i.e. there might not be any point in duplicating old backups, if you won't be able to restore them because you don't have a device that is capable of running the old version of NetApp.  I'm not picking on NetApp here, the same might be true of any NDMP capable device.  Or, still do your duplications, yet still check version to version restore compatibility, and simply be in a better position of actually knowing that you have copy on modern fresh media, and that you definitely can, or definitely cannot, restore it to your current version of storage array platform.

[Jaap_Hartog]

I am aware of the fact that the NDMP-backups can only be restored to the same type of platform that it came from.
Thus, we can easily restore data, originated from our previous EMC-NAS onto the current one, but we cannot restore the data from the LTO2-tapes (originated from a Windows-based SAN) directly onto our NAS.
We first restore it on a Windows Server and from there on move it to the NAS.

Our next NAS will, without a doubt, be again one from EMC, so I have no fear of restoring our first generation- and second generation NAS-data onto it, when necessary.

Thanks again for pointing out !

Jaap

[Mania]

Agreed with Jaap