01-28-2013 08:39 AM
i have a customer having a 10 TB of NAS data ( File server with lots of small files) backup via Fc to LTO5 drives.We have changed the daily backup type to differential but the backup size seem to be very close to the full backup size.
Is there a best approach to backup huge data i multiple stream via NDMP backup ? Any new feature on Netbackup 7.5 which i can use?
Currently using Netbackup 6.5.4 and intended to upgrade to 7.5 latest version .
01-28-2013 05:56 PM
In NDMP incrementals, NDMP host determines which files to be backed up refering NDMP dump level passed by operator and backup software. Wrong configuration may sometimes lead to such issue even if there are no significant changes to data.
Have you configured both full and differential schedule in single policy? How frequently both backup run?
01-29-2013 01:31 AM
Maybe you should look at an Archiving solution.
01-29-2013 02:54 AM
Multiple Streams does work fine but with netapps you often hit the 4 streams limit as the NDMP writer can only write a mximum of 4 streams at a time
As the earlier post says the differential backups rely on the internals of the file which works on a level basis internally recorded to determine what has been backed up and what has not
You have to be careful here as if you do sub folders as streams then it could trigger the top level folder to have its backup level changed - at this point you would not get as much backed up as you should.
There are also the DAR capabilities which may assist you with restores of individual files
If you plan to use De-Dupe in 7.5.0.4 then that release includes new stream handlers for NDMP which increase the de-duplication rates obtained.
Also note that snap mirror destination volumes always do a full backup apparently
Hope this helps