A lift-and-shift migration may require a layer-2 bridge for overlay logical switches.

A layer-2 bridge is required if overlay is used in the environment and you want to minimize downtime. A layer-2 bridge is not required if VLAN is used in the environment. A layer-2 bridge is also not required if you plan to migrate all the workload VMs in a single maintenance window and you can accept downtime during the migration.

If a bridge is required, perform the following tasks.