Starting with NSX-T 3.2.1, during the host migration step, you can add or remove a host to be migrated when there is a pause in the migration. Migration will pause if you enable the setting Pause Between Groups or if there is a failure to migrate a host.

You can add a host to a cluster before or after the cluster has been migrated, or while the cluster is being migrated. You can also remove a host from a cluster that has not migrated or is being migrated.

The host you want to add must be a standalone host in vCenter Server or in a cluster that has neither NSX-V or NSX-T configured.

Adding a host to a cluster

  1. Put the host in Maintenance Mode.
  2. For a standalone host, from NSX Manager UI, go to System > Fabric > Nodes > Transport Nodes and verify that the host is present under Other Hosts.
  3. From NSX Manager UI, go to Networking > IP Address Pools and create a new VTEP IP pool that does not overlap with the existing VTEP IP pool in the system.
  4. Click on the host and configure NSX-T to make it a host transport node.
  5. Select the appropriate transport zones.
  6. If an overlay transport zone is chosen for the host switch, choose the new IP pool that was created in step 3. Make sure that you do not choose the existing IP pool. Select an uplink profile. Do not choose the one whose name contains "VXLAN" if an overlay transport zone is chosen for the host switch.
  7. After NSX-T is installed and the status of the node is "Success", move it to the appropriate cluster in vCenter Server. Do not move the host out of Maintenance Mode.
  8. Click the Refresh button on the host migration screen so that the migration group for the cluster contains the new host.
  9. Click the Retry, Continue, or Migrate button to resume or start the migration of the cluster.
  10. vMotion VMs to the host. If any VM is moved from an NSX-V host, be sure to change the network to map the source virtual-wire to NSX-T overlay segments. For example, virtual-wire vxw-dvs-64-virtualwire-4-sid-10787-1-switch-191 must map to 1-switch-191-LS.

Removing a host from a cluster

  1. From vCenter Server, migrate all VMs off the host and enter the host into maintenance mode.
  2. If the host is in a cluster that has not started migrating, go to the next step. Otherwise, from NSX-T Manager UI, go to System > Fabric > Nodes > Host Transport Nodes. If the host has NSX configured, delete it. If the host is not reachable by NSX Manager, delete it with the force option.
  3. From vCenter Server, remove the host. Wait until the task is complete.
  4. Click the Refresh button on the host migration screen to remove the host from the migration group.
  5. Restart the host migration.