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A LUN fails to appear as a usable device during a rescan with the VMkernel log error: Peripheral qualifier 0x1 not supported (1012270)

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  • During a rescan operation, the LUN might not appear as a usable device in the VMware Infrastructure/vSphere Client or in esxcfg-mpath. 
  • You may observe a series of events similar to the following within the VMkernel logs:
ScsiScan: 839: Path 'vmhba2:C0:T1:L0': Vendor: 'Vendor' Model: 'Model' Rev: '0000'
ScsiScan: 842: Path 'vmhba2:C0:T1:L0': Type: 0x0, ANSI rev: 5, TPGS: 0 (none)
ScsiScan: 105: Path 'vmhba2:C0:T1:L0': Peripheral qualifier 0x1 not supported


The issue is resolved in ESX 4.1 Update 1 and ESX 4.0 Update 3. These messages do not appear in the VMkernel logs.

These messages indicate that the storage array is providing a non-zero Peripheral Qualifier in response to a SCSI Inquiry command for a given LUN. In the example from the Symptoms section, the storage array provides a non-zero Peripheral Qualifier for LUN 0.

There are two situations in which you may receive this message:

  • This message is returned only for LUN 0 at 5 minute intervals and there is no LUN 0 presented to the ESX host.

    : Management commands (such as REPORT LUNS) are sent to LUN 0, irrespective of whether it is available or not.

    In this case, the message can be safely ignored because the array correctly reports that the ESX host does not have access to LUN 0. However, it causes log spew and may make troubleshooting other potential problems difficult. VMware recommends that you present a LUN 0 to the ESX host to stop this spew.

  • This message is returned for LUNs besides LUN 0.

    This can be the result of incorrect storage side LUN presentation, invalid hostmode settings, incorrect or incompatible firmware versions, or other vendor specific configuration parameters. Contact your vendor and reference the
    VMware Hardware Compatibility Guide and VMware SAN Configuration Guide or iSCSI Configuration Guide to ensure that you have properly configured your storage array for use with your version of VMware ESX.

Possible return codes from SCSI SPC-3:

  • 0x0 = 000b – The specified peripheral device type is currently connected to this logical unit. However, it does not indicate that the device is ready for access by the initiator. If the device server is unable to determine whether or not a physical device is currently connected, it may use this peripheral qualifier when returning the INQUIRY data.
  • 0x1 = 001b – The device server is capable of supporting the specified peripheral device type on this logical unit. However, the physical device is not currently connected to this logical unit.
  • 0x2 = 010b – Reserved
  • 0x3 = 011b – The device server is not capable of supporting a physical device on this logical unit. For this peripheral qualifier, the peripheral device type should be set to 1Fh to provide compatibility with previous versions of SCSI. All other peripheral device type values are reserved for this peripheral qualifier. 
  • 0x4 - 0x7 = 1xxb – Vendor specific
For further detailed information, see SCSI Standards Architecture from T10.
Note: The preceding link was correct as of May 20, 2010. If you find the link is broken, provide feedback and a VMware employee will update the link.

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