Datastore "Not a known device", which makes it unable to be removed.

[NYSteve]

Hi,

     I tried removing a datastore which our SAN folks had removed the LUN from prematurely, and I'm getting the "Not a known device" message.  Is there any way to remove the reference of the datastore without that LUN being reattached (which, in this case, is not possible)?

     Thanks!

          NYSteve

[bayupw]

Hi

See this KB: VMware KB:    Unable to remove a datastore from the vCenter Server 4.x / 5.x inventory

Symptoms

Unable to remove the datastore from the vCenter Server inventory.

The datastore is grayed out.

All options for the datastore are grayed out.

Cause

This issue occurs when the datastore is removed from the ESX host before removing it from the VMware vCenter Server inventory.

Resolution

To resolve this issue, manually remove the datastore references from the vCenter Server Inventory.

Rebooting the affected hosts fix the issue in some cases.

See the "More Like This" links at the right-hand side.

If you are using NFS, check this KB: VMware KB: Unable to remove an inaccessible NFS datastore with Storage I/O control enabled

Thanks,

Bayu

[CaribouSolution]

Same problem here.

Go through your hosts and Rescan Storage.