Cold Migration
This is my preferred method when you don’t have shared storage. However, it does require that you have paid licensing for ESXi and a VCenter server. Also, both hosts must be managed by the same VCenter server.
At a high level, here are the steps:
From the vSphere client:
- Shutdown the VM you intend to migrate
- Click on ‘Migrate…’
- Select ‘Change both host and datastore’
- Select the destination host and datastore
- Click Finish and wait…
All the vmdk’s, etc are copied to the datastore on the new host. After copied, the files are removed from the old host. VCenter takes care of unregistering the VM from the old host and registering on the new host.
Compared to some of the other methods I’ll discuss, this method retains the nic and associated IP settings through the move. So, DC’s and Exchange servers are less likely to be confused after the move.
A downside of this process is that it doesn’t have a quick failback method. Moving back to the original host would require another copy. Also, if you’ve upgraded VM hardware and VMWare tools after the move and your new host is on a newer version of ESXi, chances are the VM won’t be backwards compatible to run on the old host as-is.
Another downside is that this process doesn’t have a method of determining how long it will take it to complete.
We’ll continue to explore migration methods for this scenario in Part 2.