2012-01-26 12:33 AM
When creating a new Protection relation automatically at the destination ist created a qtree. Is there and option available that instead to create every thime a new volume instead volome/qtree ? So that we get for every Vol with luns at the target as well a volume and no qtree ?
2012-01-26 10:56 AM
If you are backing up data (using a Backup connection, which translates to SnapVault or Qtree SnapMirror on the storage system), ONTAP always requires a qtree as a destination. There's no way to avoid that. ONTAP won't back up to a bare volume.
There are options to control how many qtrees we put in a destination volume. If you set the options "pmMaxQsmRelsPerSecondaryVol" and "pmMaxSvRelsPerSecondaryVol" to 1, we'll always create a new destination volume per source qtree.
Out of curiosity, why do you want to do this? Is the qtree causing a problem? Are you trying to avoid having multiple LUNs in a single volume?
2012-01-30 01:29 AM
Yes exactly. I try to avoid having multiple lun's on the destinations vol’s as may the usable space is overfilling target to fast if multiple LUN’s share same volume in term of Snap-Shot. We use snap mirror in DPM.
Secondly is just simpler to have an 1:1 relation as 1:n. As anyway is best way to have for each LUN a separate volume we try to change the default behavior qtree. Of course we cloud live with the fact that dpm ist creating in vol a qtree for each entity but as we like to isolate every LUN anyway I was asking why not directly change default behavior of dpm that he is not going to create qtree at all.
On command line there you can create at least with snap mirror volume to destination without an qtree on target (volume snap mirror). The goal is to use the snapmirror compression as well with dpm and what I know snap mirror compression is only working on volume level not on tree level.
So this is my goal to have lunvol to lunvol 1:1 snapmirror without any qtree on destination and all with snapmirror compression (unfortunately this option not selectable in dpm).
2012-03-23 01:01 PM
The option you mentioned is a hidden option. In order to see it you will have to first set it using the below cli.
dfm option set pmMaxQsmRelsPerSecondaryVol=20. The default value for this options is 50.