Upgrade of ESX 2.5 to ESX 3.5

[ikirkum]

We have VMware Farm of 30 Hosts with ESX 2.5 version, Currently working on plan to upgrade ESX 3.5. I already browsed documents like upgrade guide and other best practises. Now we planned to execute using migration approach with a new datastore (using Vmware converter tool in the back end).

Can we directly migrate machines from esx 2.5 to esx 3.5 .? Virtual to Virtaul Conversion- any limitations . i can understand the time consuming

or

Evacute all the VM's in the esx 2.5 host and do inplace upgrade to 3.0.1 and do an update 3.5 bring back VM to 3.5?

one more doubt can we directly upgrade esx server host 2.5 to esx server host 3.5 - i heard people saying you need to upgrade to esx 3.0.1 and then to esx 3.5.

Suggestion and advice are welcome!

[LarsLiljeroth]

Yes you can do a hot migration of the server from 2.5 - 3.5 but you still need to plan for down time to install Vmware Tools.

We just finished an upgrade of 10 hosts and 250 guests. But we used Vmigrator from Vizioncore. The cool thing with this tools

is that you can schedule the cutover time and it will also do the Tool sinstallation for you. The price for the tools is OK.

Another cool thing is that your source server is not still in place. So if you have issues you can start that one up again.

If you use the "Vmotion" migration your server will be moved and can't move back to 2.5

[VirtualNoitall · Accepted solution]

Hello,

Why not wipe and rebuild your ESX hosts as 3.5 ( instead of upgrading )? We never upgrade. We do reinstalls, Just seems more straight forward and cleaner.

[LarsLiljeroth]

I agree... clean install is the way to do it ... but still need to migrate the VMs..