For Multihost Clustering Using Clustered Virtual Disks, the LUN No Longer Requires a Single Path

Products

• VMware vSphere ESXi

Issue/Introduction

The documentation indicates that for multihost clustering using clustered virtual disks, the LUN must have a single path. Is this still true for ESX Server 2.5 and later releases?

Environment

VMware ESX Server 2.5.x

Resolution

The clustering configuration table displayed at www.vmware.com/support/esx25/doc/admin/esx25admin_cluster_setup_esx.html#999125
indicates that for multihost clustering using clustered virtual disks, "The LUN must have a single path." This was true for ESX Server releases prior to 2.5, but it is no longer a requirement.

Here is the table from the Administration Guide with the corrected information. This table summarizes additional, important points for using Microsoft clustering software with ESX Server.

Area	Component	Single-Host Clustering	Multihost Clustering
Non-clustered disks	Virtual machine and swap (paging) file	Must be on local storage, not on a SAN Must be a non-clustered disk
	Non-clustered virtual disks (.vmdk)	Must reside on a public VMFS volume Must use VMFS label notation Virtual adapter must be set to shared mode = none
	Non-clustered raw device (disk) mapping	Revision must be ESX Server 2.5 or higher Must reside on a public VMFS volume Must use VMFS label notation Disk must be in persistent mode DeviceType must be scsi-nonpassthru-rdm or scsi-passthru-rdm
	Non-clustered raw device (disk)	Use raw device mapping instead, if on ESX Server 2.5 or higher
Clustered disks	Clustered virtual disks (.vmdk)	Must use VMFS label notation Virtual adapter must be in shared mode = virtual The LUN must host only one VMFS file system The VMFS volume must be dedicated to the cluster Must reside on public VMFS volume	Must have been created withvmkfstools -z Must use the vmhba:: notation, not the VMFS label notation. Virtual adapter must be set to shared mode = physical Must reside on its own physical LUN The LUN must host only one VMFS file system The shared virtual disk must be the only file on this VMFS volume The VMFS volume must be in shared mode The VMFS volume must have only one physical extent
	Clustered non-pass-through raw device mapping	Revision must be ESX Server 2.5 or higher Must reside on a public VMFS volume Must use VMFS label notation Disk must be in persistent mode DeviceType must be scsi-nonpassthru-rdm Virtual adapter must be set to shared mode = virtual	Not supported