ONTAP Discussions

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

rtriana
5,722 Views

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.

5 REPLIES 5

bertaut
5,722 Views

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,

aborzenkov
5,722 Views

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

paulstringfellow
5,722 Views

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.

aborzenkov
5,722 Views

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).

bertaut
5,722 Views

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,

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