NDMP Restores and Symbolic Links

[James-FSI]

Hello.

We are running a Windows 2003 R2 Server with NetBackup 6.0MP7.

We have recently implemented the NDMP backup feature to backup our Oracle data from a NetApp filer.  The backups are running well, and restores work fine, but any symbolic links are not restored at all.

I have seen where it is possible to re-enable this feature on a UNIX NetBackup server, but I cannot find a way to do so for a Windows server.

Can you please point me in the right direction?

Thanks

James

[Darren_Dunham]

I've not heard of this before.

Unlike windows or unix backups going through the netbackup client, there's not as much control of NDMP backups.  The NDMP host is responsible for what to do with the data, and I don't know any way to signal to the filer that it should or shouldn't deal with symlinks.   You'll note that the options are all grayed out in the restore box.  That's nothing to do with windows master versus UNIX master, that's just because you're doing an NDMP restore.

I have no specific ideas for you.  I might try doing a special (read "small") backup that has some symlinks in it, and then doing a restore just of that to verify the behavior.  Then I'd look in the restore logs on the NetBackup server and see what it said.  Did it say the restore was successful?

I just tried it (admittedly UNIX master, but should be no difference), and I can see the individual files in the restore log, and sure enough they're in the restore directory.

15:17:37 (152378.001) INF - Restoring NDMP files from /vol/testvol/report/ to /vol/testvol/RESTORE
15:17:38 (152378.001) DAR enabled
15:54:43 (152378.001) NDMP restore successful from path /vol/testvol
15:54:43 (152378.001) /vol/testvol/report/#media_report#
15:54:43 (152378.001) /vol/testvol/report/.#media_report
15:54:43 (152378.001) /vol/testvol/report/report.csv
15:55:34 (152378.001) Status of restore from image created Sun Feb  1 03:00:04 2009 = the requested operation was successfully completed

15:55:34 (152378.xxx) INF - Status = the requested operation was successfully completed.

(.#media_report# is a symlink, it is in the RESTORE directory, and it is correct).

Are you restoring to the same volume?  If not, are there any differences between source and destination volumes (or filers)?

-- 

Darren

[James-FSI]

This is the complicated part.

we are attempting to restore to a different filer, different volume.

I have not tried to restore to the same volume.  I will try today and see.

[James-FSI · Accepted solution]

Looks like this may be the fix...  I am going to try it now and should know within a couple of hours..

Create the following DWORD value

HKLM\Software\Veritas\NetBackup\CurrentVersion\Config

SKIP_RESTORE_TO_SYMLINK_DIR

Value = 0

I am going to try and post the results when finished

[Darren_Dunham]

On a normal client, that being set to 1 would prevent any file from being restored to a directory which has a symlink somewhere along the path.  It wouldn't prevent a symlink itself from being restored.

On an NDMP client, it should have no effect (the NDMP host can't read your registry to even know it's set).

Can you do a test backup/restore and post the contents of the restore log?  Do the symlink names even appear in the restore log?

-- 

Darren

[James-FSI]

Thanks Darren.

I was just doing exactly that and this registry key resolved the issue.  All symbolic links are now restored to the test restore volume.  NetBackup was actually skipping those files without the setting.

We have successfully mounted the Oracle database after the restore. 

I am going to mark this is resolved.

Thanks for your assistance.