Accessing existing VMFS storage via iSCSI

[ericsl]

Hello All,

In a test environment I am attempting to access an existing VMFS Datastore via iSCSI.

In Storage Adapters I clicked Rescan. The SCSI target shows up correctly. However, it does not show up in Storage, even after clicking Refresh.

If I click Add Storage and select Disk/LUN I can see the storage device, clicking Next shows the Primary Partition as VMFS. Of course if I click Next again this will format it as a new Datastore, something I don't want to do.

How can I get this existing VMFS volume to show up in Storage?

TYIA,

Eric

www.mymanagedbackup.com

[JeffDrury]

Is this storage on a SAN? Are you mounting a snapshot of an existing datastore? Are you trying to mount to the same ESX host as the original data or another ESX host? Can you provide more details?

[Lightbulb · Accepted solution]

Have you tried setting enableresignature to 1 in the advanced settings (see Attached) and then rescanning.

[ericsl]

Jeff,

Sorry, here's more detail.

Storage is on a SAN, American MegaTrends StorTrends.

The iSCSI target is a writable snapshot of an existing store, but it has a new target assigned to it (and shows up separately in Storage Adapters).

I am attempting to mount from the same ESX host.

As an FYI, previously in testing volume snapshot rollback capabilty of the SAN I deleted all of the data in the Datastore via ESX Datastore Browser, removed the Datastore from ESX, rolled back to a previous snapshot in the SAN, rescanned the VMFS volumes in Storage Adapters and the Datastore re-appeared (as expected!).

Now I am trying to mount a writable snapshot of that same volume for testing purposes...

Eric

[Lightbulb]

Disregard my post then

You may want to read

http://www.yellow-bricks.com/2008/12/11/enableresignature-andor-disallowsnapshotlun/#more-1213

[ericsl]

Lightbuld,

That did the trick, and the article you referenced looks good as well. The volume now shows up, as well as some others that were previously hidden!

Eric

[Lightbulb]

Glad to hear it. You should review the articale and ensure to set the Host back to the default values.

[JeffDrury]

Lightbulb beat me to it. If you want to mount an existing VMFS filesystem the you need to enable resignaturing. This can be dangerous on some SAN systems depending on their technology. Also you want to be careful about mounting the same filesystem multiple times on the same ESX host or cluster. Once you are done with this test you will likely want to go back and disable resignarturing for normal operations.