ESX4.1 and ESXi5.1 in the same HA/DRS Cluster

[rz1]

Hello all,

In the vSphere 5.1 release notes, it states: "vCenter Server 5.1 can manage ESXi 5.x hosts in the same cluster with ESX/ESXi 4.x  hosts."

We have already upgraded vCenter/Update Manager from 4.1 U2 to 5.1, and are now going to work on the ESX hosts.  The plan is to take a host out of the cluster, re-install it from scratch with ESXi 5.1, and then put it back in the cluster.  There's a dozen ESX 4.1 hosts in our current HA/DRS cluster.  We'll do one at a time and in a week or so should be all at 5.1.

I was wondering if anyone has run into any issues or has any comments on having both ESX 4.1 and ESXi 5.1 in the same cluster.

Thanks for your help...

[KamilAzmer]

In the vSphere 5.1 release notes, it states: "vCenter Server 5.1 can manage ESXi 5.x hosts in the same cluster with ESX/ESXi 4.x  hosts."

Yes, you may managed lower ESXi 5.x version if your vCenter Server version is higher than ESXi.

The plan is to take a host out of the cluster, re-install it from scratch with ESXi 5.1, and then put it back in the cluster.  There's a dozen ESX 4.1 hosts in our current HA/DRS cluster.  We'll do one at a time and in a week or so should be all at 5.1.

I was wondering if anyone has run into any issues or has any comments on having both ESX 4.1 and ESXi 5.1 in the same cluster.

There are no issue running both in same cluster, but there functionality and advanced config not same between 4.1 and 5.1, better to have new cluster and migrate the VMs into new cluster with latest version.

Just my one cent.

[aravinds3107]

Just to Add : Make sure you DONT upgrade the VMFS and VM Hardware version to the latest version until you complete the upgrade of all the ESXi host to 5.1