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Is a hot vfiler move possible ?

The Ontap manual says :

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How migrating a vFiler unit affects clients

Migrating a vFiler unit to another storage system on the same subnet has the following affects.

  • NFS volume-level mounts move transparently
  • NFS qtree-level mounts must be remounted
  • CIFS clients need to be reconnected
  • LUN access continues uninterrupted Although an iSCSI host is briefly disconnected from the source vFiler unit, an initiator hides this brief disruption from applications accessing the LUNs. To the applications, access continues without interruption

So this would mean  that it 's not possible to do a "hot" migration of nfs only vfilers (mostly clients mount on qtree level) ?

By hot migration I mean clients are active and have nfs mounts from the migrating vfiler. A few messages/some minutes with "NFS not respondig" is not aproblem if after the migrate NFS to the clients is back to normal.

thanks for response ,

Walter Talloen   

Is a hot vfiler move possible ?

The documentation is a little unclear.  To clarify, if the vFiler owns only the qtree, not the volume then qtree level mounts must be remounted.  In MOST cases, the vFiler owns the volume.  A vFiler can be assigned either volumes or qtrees.  A best practice is to assign volumes.  When the vFiler owns the volume, both volume and qtree mounts stay mounted.  When the vFiler owns the volume the vol fsid moves and all vol/qtree mounts stay intact when they are moved with the file handles to the target. 

So, if you see under "vfiler status -a" that the vfiler is assigned volumes /vol/volname and not qtrees... (qtrees in volumes are automatically owned by the vfiler since below the volume assignment) it will keep mounts.

Now to the outage part... vfiler migrate does not guarantee a failover time.  It runs until completion as long as it takes the final mirror and start on the target.  This may or may not complete in your nfs timeout window.  To get a guaranted migration within 120 seconds (using semi-sync snapmirror and the automation to fail back to source if not complete in 120 seconds), we need to integrate with OpsManager (OnCommand) and use Data Motion (won't work on 8.0, a 7.3 feature and soon an 8.1 feature).

Is a hot vfiler move possible ?

Hi Scott ,

Thanks a lot for the very clear explanation .

Is it possible to explain more " integrate with OpsManager (OnCommand) and use Data Motion (won't work on 8.0, a 7.3 feature and soon an 8.1 feature)."

o. What is the "7.3 feature" ?

o. OpsManager - another user interface ...

Is there a white paper explaining the specifics off Data Motion  ?

I found TR-3326 explaining the charastics off Sync and semi-sync SM

Thanks,

Walter 

Is a hot vfiler move possible ?

TR-3814.  The GUI you use is the NetApp Management Console (NMC) which you download and install from the Operations Manager (web gui) setup menu and NMC is a java app that runs on Windows or Linux.