Migrate VMs from old cluster into new one with new vCenter Appliance

[aj800]

I'm looking for advice on the best path forward for migrating VMs in an old vSphere environment to a new one.

We have a 6.5 environment with a few ESXi hosts (running on Sandy Bridge family CPUs) in a cluster there... and rather than upgrading the VCSA in place, we decided to create a whole new environment running 7.0U3 on our newer servers.

During setup of the new environment, I deployed a new VCSA on one of the new hosts (Cascade-Lake family CPUs), then created a cluster (without configuring EVC) for the new hosts, then added the hosts to the environment (at the Datacenter level, since the VCSA was running on one of the hosts and could not be put into  maintenance mode), then dragged the hosts into the cluster (you can add a host to a cluster while it is not in maintenance mode this way).  I now have a VCSA (VM) running on one of those hosts in that cluster.

EVC is currently disabled in the old environment.  I am assuming that since the old hosts are currently operating on Sandy Bridge CPUs, that compatibility might be an issue if we simply created a new separate cluster and enabled EVC on it set to Sandy Bridge, and brought in those old hosts with the VMs on them, added them to the vDS, and then tried to migrate the VMs over to the new Cascade Lake family CPU hosts.  You CAN migrate between clusters, as long as they share the vDS connections and same networks (from what I recall), even with different uplinks to the hosts.

Based on what I've read in this VMware KB article , I plan to:

1) Rename existing vSphere 7 ESXi cluster (from "Cluster_A" to "Cluster_A_Tmp" -This can be done on the fly with active hosts and running VMs, so I need to do this first since I expect to move the hosts currently in it to a new cluster with EVC enabled under a different but correct and permanent name so I would not need to move them back from a temporary cluster that is configured correctly).
2) Create a new cluster in vSphere 7 environment ("Cluster_A"), enable EVC and configure it for Sandy Bridge
3) Put the vacant hosts in Cluster_A_Tmp into maintenance mode, then drag them from "Cluster_a_Tmp" to the new Sandy Bridge cluster (Cluster_A), and exit maintenance mode.
4) Note the location of the .vmx file and ESXi host the VCSA is running on in Cluster_A_Tmp, shut the VCSA down, then go directly to the client of that host and remove the VCSA from inventory.
5) Go to the client of one of the new hosts now in Cluster_A, add the VCSA to its inventory (right-click the .vmx file), and power it on.
6) From the vSphere Client, put the remaining vacant host in Cluster_A_Tmp into maintenance mode, drag it from Cluster_a_Tmp to Cluster_A, then exit maintenance mode.
7) In the vSphere 6.5 environment, shut the running VMs down on each host in the old cluster first ("Cluster_X") so that each host can be put into maintenance mode and removed from Cluster_X and removed from the vSphere 6.5 inventory.
😎 In vSphere 7, create "Cluster_B", enable EVC and set it to Sandy Bridge.
9) Add the old hosts to the Sandy Bridge EVC cluster (Cluster_B) and add their uplinks to the vSphere 7 distributed switch.
10) Power on the VMs, then migrate them to the hosts in Cluster_A.
11) Delete the empty "Cluster_A_Tmp", and, once all VMs have been vMotioned from the 6.5 in Cluster_B to the 7.0 hosts in Cluster_A, the 6.5 hosts in Cluster_B can be powered off, removed from inventory and the cluster deleted.

Is this about right?  Any assistance would be appreciated.  Thanks