Force mounting a LUN on an ESXi host fails with the error: duplicate extents found

Products

• VMware vSphere ESXi

Issue/Introduction

• Cannot force mount a LUN with command esxcli storage vmfs snapshot mount -u VMFS_UUID on the ESXi host
• Forcing to mount a LUN with command esxcli storage vmfs snapshot mount -u VMFS_UUID on the ESXi host fails
• You see the error:

VMFS UUID/label: 5419####-########-####-##########88/LUN01
Can mount: No (duplicate extents found)
Can resignature: No (duplicate extents found)
Extent name: eui.00255c3a2285016e:1 range: 0 - 547583 (MB)
Extent name: eui.00255c3a2285001a:1 range: 0 - 547583 (MB)

• Any attempt to re-signature via the Add Storage wizard indicates of a complete format of the affected LUN

Environment

VMware vSphere ESXi (All Versions)

Cause

This issue occurs when two different LUNS with their own unique NAA IDs have the same VMFS signature.

 

For example:
 

VMFS UUID/label: 5419####-########-####-##########88/LUN01
Can mount: No (duplicate extents found)
Can resignature: No (duplicate extents found)
Extent name: eui.00255c3a2285016e:1 range: 0 - 547583 (MB)
Extent name: eui.00255c3a2285001a:1 range: 0 - 547583 (MB)

Note:
 

eui.00255c3a2285001a was the original LUN

eui.00255c3a2285016e was the snapshot LUN

Resolution

1. Un-present one of the affected LUNs from the ESXi host. For more information, see How to detach a LUN device from ESXi hosts
2. Rescan all HBAs as required.
3. Attempt to re-signature the other affected LUN. For more information, see Troubleshooting LUNs detected as snapshot LUNs in vSphere.
4. Present the other affected LUN on the same ESXi host. Confirm that this LUN is visible in the Storage Adapters device list. Rescan all HBAs as required.
5. Attempt to re-signature the other affected LUN.

If the issue persists:

• Collect VMware Support information.
• File a support request with Broadcom Support and quote this Knowledge Base article ID (345232) in the problem description.