LUNs are missing after upgrading the hosts to ESXi 6.5

Products

• VMware vSphere ESXi

Issue/Introduction

The purpose of this article is to bring back the LUNs that were present before the upgrade.

Symptoms:

• Upgrading ESXi hosts to 6.5 causes LUN not to be seen.
• In the vmkernel.log you see entries similar to:
  

  YYYY-MM-DD HH:MM:SS cpu5:65786)ScsiUid: 403: Existing device naa.0000000000000000000000000f already has uid vml.0000000000000000000000000f 
  YYYY-MM-DD HH:MM:SS cpu5:65786)ScsiDevice: 4163: Failing registration of device 'naa.0000000000000000000000000f '
  YYYY-MM-DD HH:MM:SS cpu5:65786)ScsiDevice: 4165: Failed to add legacy uid vml.0000000000000000000000000f on path vmhba4:C0:T2:L1: Already exists
  YYYY-MM-DD HH:MM:SS cpu5:65786)ScsiEvents: 545: Event Subsystem: Device Events, Destroyed!
  YYYY-MM-DD HH:MM:SS cpu5:65786)WARNING: NMP: nmp_RegisterDevice:851: Registration of NMP device with primary uid 'naa.0000000000000000000000000f ' failed. Already exists

   

Environment

VMware vSphere ESXi 6.5

Cause

This issue occurs because the registration of the device fails if it has paths with different LUN IDs.

Resolution

Currently, there is no resolution.

To work around this issue, unpresent and then present the LUN with the same LUN ID.

 

Note: For multipathing to work as expected, VMware recommends that each LUN must present the same LUN ID number to all ESXi hosts. For more information, see the ESXi Fibre Channel SAN Requirements section of the vSphere Storage Guide on page 39.

 

Additional Information

Impact/Risks:
Requires Reboot