Courtesy of some helpful engineers over at NetApp monitoring the list ;)
This parameter is indeed controlled by NetBackup, not via the policy includes, but by the server-level parameter SIZE_DATA_BUFFERS_NDMP on the NetBackup master server.
These pages describe the parameter to change:
http://www.symantec.com/business/support/index?page=content&id=TECH51967 http://www.symantec.com/business/support/index?page=content&id=HOWTO5615...
By cranking that value up to 256kb from the default 64kb, I see 'record size' has changed in the ndmpd logs, and the write speed on our FC NDMP backups has doubled!
Sweet!
On Tue, Mar 6, 2012 at 4:38 PM, Mike Thompson mike.thompson@gmail.comwrote:
Hey all,
I'm trying to increase performance of fiber channel NDMP backups we have going to a remote tape robot (bridged over WAN via some Cienna gear).
I would like to try increasing the blocking factor that the filer uses when writing to tape over NDMP.
I'm running Ontap 8.0.1 c-mode, with NetBackup 6.5.
None of the docs explain how to do this, but there is mention of blocking factor in the Data Protection manual. All it says is that block size up to 256KB is supported, and that the variable MOVER_RECORD_SIZE is what controls that.
It appears that you can send variable settings to NDMP by using 'set variable=value' at the top of your includes list in the backup policy in NetBackup.
I have tried putting 'set MOVER_RECORD_SIZE=256' at the top of my includes list, and running the job, but I get this in the /mroot/etc/mlog/ndmpd.log:
INFO: Pass through of unknown START BACKUP variable MOVER_RECORD_SIZE with value 256
I have also tried setting the variable DATA_BLOCK_SIZE, but get the same result.
So the question is, how do I set the blocking factor for NDMP backups?