ESXi 5.5 supports clustering using MSCS across virtual machines. vSphere 5.5 supports these configurations:
- Clustering MSCS Virtual Machines on a Single Host (CIB)
- Clustering MSCS Virtual Machines Across Physical Hosts (CAB)
- Clustering Physical Machines with MSCS Virtual Machines (N+1
Notes:
- MSCS applies to Microsoft Cluster Service with Windows Server 2003 and Failover Clustering with Windows Server 2008 and 2012.
- Support for Windows 2012 R2 Failover Clustering with shared storage configurations requires vSphere 5.5 Update 1 or later.
These restrictions apply to all MSCS clusters running in a vSphere environment:
- Mixed protocols across cluster nodes are not supported. For example, FC on one cluster and FCoE or iSCSI on another node.
- Mixed mode ESXi configurations are not supported. For example, one node running ESX 5.5 and another running ESX 5.1.
- Rolling upgrades of cluster nodes pre-5.5 to 5.5 are not supported. The MSCS Cluster must be shut down to apply the ESXi host upgrade.
- Mixed CIB and CAB cluster configurations are not supported.
PSP_RR support
In vSphere 5.5, round robin policy is now supported for disks engaged in MSCS clustering.
However, these restrictions apply:
- Cluster in a Box (CIB) configuration is now supported, and uses Virtual Reservations.
- RDM datastores should be in physical compatibility mode.
- Supported on Windows 2008, Windows 2012 and Windows 2012 R2 server guest operating systems only.
- Supported on Cluster Across Boxes (CAB) and N+1 configurations.
- Shared disk (Quorum OR Data) must be provisioned to guest in pass-through RDM mode only.
- Windows 2012 and Windows 2012 R2 cluster validation may fail with "resource busy" error while using PSP_RR. This error can be ignored.
Note: Cluster nodes having PSPs configured in mixed mode are supported. For example, in a 4-node cluster, one node can be configured with PSP_FIXED and the other three nodes can be configured to use PSP_RR.
iSCSI support
In vSphere 5.5, native iSCSI support is introduced.
- All the cluster configurations CAB, CIB and N+1 are supported with iSCSI.
- iSCSI Storage Adapter support:
- Software iSCSI
- QLogic, Emulex and Broadcom hardware iSCSI adapters
- Mixed mode iSCSI initiator (cluster having hardware and software iSCSI initiators) is supported.
- Up to 5 node clustering is supported for Windows 2008 SP2 and above.
However, this restriction applies:
- Supported only on Windows 2008 R2 SP1 and above, Windows 2012 and Windows 2012 R2 server guest operating systems. (Windows 2012 R2 requires vSphere 5.5 Update 1 or later)
FCoE support
In vSphere 5.5, native FCoE support is introduced.
- All the three cluster configurations CAB, CIB and N+1 are supported with FCoE.
- FCoE Storage Adapter support:
- FCoE Software Adapter
- FCoE Hardware Adapters
- Up to 5 node clustering is supported for Windows 2008 SP2 and above.
However, these restrictions apply:
- Supported only on Windows 2008 SP1, SP2, R2, Windows 2012 and Windows 2012 R2 guest operating system. (Windows 2012 R2 requires vSphere 5.5 Update 1 or later).
- Mixed mode FCoE initiator (Cluster having hardware and software FCoE initiators) is not supported. All hosts must be running same FCoE initiators.