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Can a NetApp LUN be mounted r/w by one host and read-only by another host?

Question for Communities:

Can a NetApp LUN be mounted as a regular read-write LUN by one host and read-only by another host?    If so, how can this be implemented?

Rick

PS.  This is for a customer.

Re: Can a NetApp LUN be mounted r/w by one host and read-only by another host?

Hello Rick,

Yes you can have such scenario with LUNs inside snapmirrored volumes. On the primary, the mapped LUN(s) will be rw, on the secondary, the replicated LUN(s) will be ro. Make that the igroups, WWNN & zoning are done right.

Regards,

Re: Can a NetApp LUN be mounted r/w by one host and read-only by another host?

NetApp does no care how many hosts have access to LUN. It is really a question whether your host filesystem supports it.

Re: Can a NetApp LUN be mounted r/w by one host and read-only by another host?

Hi Rick,

Depends what you are trying to do really I’d say…

If you want multiple systems to access the active file system then this is an operating system thing…. However if you just want to mount snapshot copies so you can read data from them for recovery purposes for example then just mount the snapshot on another system.

Ensure you use snapdrive as this will help immensely.

Re: Can a NetApp LUN be mounted r/w by one host and read-only by another host?

Nitpicking.

It is normally not possible to directly mount snapshot copies, because they are read-only and even when mounting ro host needs to perform some filesystem recovery. So it necessary to create writeable clone (LUN clone or flexclone).

Re: Can a NetApp LUN be mounted r/w by one host and read-only by another host?

You are both making valid points; one can leverage any of the previously stated solutions (flexclone - snapshot ro until split, snapmirror - LUN ro at destination vol, mounting ro snapshots using snapdrive). In either case, using snapdrive to either mount LUNs inside snapshots or to manage the LUNs is the recommended course of action.

Regards,