snapshot

[RATNATHURAI]

This question must have asked by someone else here.

As I understand  that the snapshots are taken at volume level not at lun level .

vol status shows that nosnap=on, this means that no snap sched runs for that volume or LUN.

If we want snap shot for lun  then we can take snapshot at LUN level using snapdrive not at ontap.

I am correct ?

[martin_fisher]

No - A LUN is created within a volume on ONTAP. If nosnap is set to on, how would snapdrive create the snapshot of a LUN in a volume that wouldnt let it?

Snapdrive issues the commands to ONTAP to create the snapshots of the LUN's, at a given time, date etc. It just presents these options, along with others, in the form of a nice GUI.

It also have the ability to run other application commands that ONTAP doesnt, such as the ability to quiesce a database, before taking a snapshot, so the data is in a consistent state.

[cscott · Accepted solution]

"nosnap on" tells the system not to take any automated snapshots.  Snapdrive actually runs the snap create command, which should work on a volume with nosnap on..

It is the recommended process when using snapdrive, because system generated snaps can cause issues - https://library.netapp.com/ecmdocs/ECMM1278903/html/admin/bk_rest3.htm

To be extra sure this is the case I have logged into a lab filer, ran "vol options XXXXXXX nosnap on", then run "snap create XXXXXXX test", the snapshot was created without issue.  I also double checked the man page:

nosnap on | off

               If this options is on, it disables   automatic

               snapshots on the volume.  The default set-

               ting is off

-Scott