Our current VMware environment includes 4, ESXi 5.1 host servers running 58 virtual machines.
For whatever reason, the previous VMware Admin, did not upgrade VMware and we are now getting ready to do a complete hardware refresh with new physical host and SAN environment.
Since there is no upgrade path from 5.1 to 6.5a, we are going to do a complete new installation of VMware and vCenter.
My question is, will it be possible to migrate our virtual machines from the 5.1 to the new environment or do we have to upgrade the current environment to 5.5 or 6.0 first?
If the virtual machines from your ESXi 5.1 is stored on shared storage, you can present that LUNs (volumes) to your new hosts, and then shutdown the virtual machine at the 5.1 host, register the virtual machine at the 6.5 host and then power on the virtual machine, and if you want just migrate the virtual machines from the old datastores to the new datastores.
This is only one of possible approach. Of course upgrade your hosts to version 5.5 is another approach, but it may require additional administrative effort.
Present the old luns to new hosts
You can power off VMS from 5.1
Register VMs on 6 .x and do storage vmotion to new LUNs , if you have enough down time you move in powered off stat that will more faster for moving .
With out Down time
Check the below compatibility matrix - Existing esxi supports to new vcenter you can proceed this
Present old volumes to new hosts
add new hosts to new vc
add old esxi hosts to new vc
do live migration of vms (Storage vmotion license required for live migration )
Hi RAJ_RAJ, unless I'm missing something you cannot add ESXi 5.1 to a vCenter 6.5 see: VMware Product Interoperability Matrixes
I agree that we cannot add ESXi 5.1 to a vCenter 6.5 , in the image 6.5 not clear properly
Also I mentioned # "Existing esxi supports to new vcenter you can proceed this"
We did something similar recently with a 5.1 environment. We built a new 6.0 environment, connected the hosts to it as they are still supported by 6.0. Then upgraded the hosts to 6.0. Migrated the 6.0 vCenter to VCSA 6.5 and upgraded the hosts again to 6.5. Job done
We have the same problem we have upgraded our environment to vSphere 6.0. This is a better way other workaround if u can afford a downtime shutdown VMs remove them from Inventory but keep it on a shared storage, install new ESXi and present those LUNs again. Boom here u go we have had did this in one of our environments.