We have an existing environment of 7 ESX 3.5 Update 5 hosts and an EMC CX3-10x iSCSI SAN. We are going to decomission 2 of the ESX hosts and replace them with newer hardware and ESXi 5.1 hosts. We realize we will no longer be able to manage these ESXi hosts from our Virtual Center 2.5 console but these two hosts will be running a minimal number of VMs (Exchange 2010 multi-role) that do not utilize VMotion, HA, or DRS.
Our understanding is that ESX5.1 can see and utilize VMFS-3 datastores. Is it correct that once we have connected the new ESXi 5.1 hosts to our SAN and they can see all of the existing LUNs that we should be able to shut down the VMs on the two ESX 3.5 hosts and start those VMs on the ESX 5.1 hosts?
Has anyone experienced any issues running ESXi 5.1 with VMFS-3 datastores?
Some of the existing VMFS-3 datastores could be upgraded to VMFS-5 because they are only used by the VMs that will be running on the ESXi 5.1 hosts. But, some of the existing VMFS-3 datastores will not be upgradeable because they are used by VMs running on the other ESX 3.5 hosts. In other words, can a single VM have virtual disks that run on both VMFS-3 and VMFS-5 datastores at the same time?
Thanks,
Jay