Datastore unmount or delete - whats the difference?

[macgreen]

On the vsphere 4.1 client I have dozens of datastores.

They are all SAN FC attached.

Right click a random datastore in either Host >configuration > Storage or Inventory > Datastores view

and there is the option to delete on other random datastores there is the option to unmount.

I cannot see any difference amongst any of the datastore's configuration.

They are all VMFS 3 and version 3.31 file systems

When I unmount a datastore it gets removed. There is no option to re-mount.

There appears no consistency however on the options presented on right click - either unmount or delete..

Anyone care to enlighten why this happens or what the unmount option is for, when in the client you cannot remount on a host.

My environment:-

vSphere 4.1 :

• ESX 4.1 Servers

• vCenter Server 4.1 (VM) :

- Windows Server 2008 64bit

- MS SQL 2005 (VCDB/VUMDB)

• NetBackup 6.5.5

- VCB 1.5 U2

• FC SAN

[athlon_crazy]

Delete is for VMFS while Unmount is for NFS datastore. Delete will totally remove the VMFS, while unmount NFS will only unmount the datastore without deleting information on the share.

[macgreen]

Have no NFS datastores. All VMFS.

My environment:-

vSphere 4.1 :

• ESX 4.1 Servers

• vCenter Server 4.1 (VM) :

• Windows Server 2008 64bit

• MS SQL 2005 (VCDB/VUMDB)

• NetBackup 6.5.5

• VCB 1.5 U1

• FC SAN

[Nonna]

I 've got the same problem in my environment - FS SAN, vCenter 4.1 and ESX 4.0U2.

When I tried to delete a datastore - worning message was - do you really want to unmount a force mounted datastore?

This reminded me that when we did a storage failover - esx 4.0 saw all my LUNs as snapshots, so I had to force mount LUNs on each host and modify ESX config to force mount themafter every boot (using esxcfg-volume -M <UUID> command on each host. (*instead of resignaturing datastores)

Have you had any SAN fail over? You should try to check your ESX config to see if you are force mounting your datastores

This link might be helpful

http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&externalId=1015986&sliceId=1&docTypeID=DT_KB_1_1&dialogID=50939580&stateId=0%200%2050941538

[GJAY01]

Old topic, but just confirming this is exactly the behavoir I see in my environment.  Snapshot/replica luns that are force mounted have the "unmount" option rather than "delete."   VMFS is not destoryed during the unmount option, if you run "esxcfg-volume -l" after completing it you'll see the lun available again for mounting and/or resignaturing.