Test failover could failed due to below error:
com.vmware.h4.cloud.api.exceptions.VappNotFoundException: vApp 'xxxxxx' was not found.
or
com.vmware.h4.replicator.api.exceptions.InstanceNotFound: An instance with id 'replica-xxxxxx' was not found.
These error could be caused due to long time task waiting:
com.vmware.h4.api.error.exceptions.client.ReadTimeoutException: Socket read timeout.
If the latest instance is chosen, the test failover run very slow than that with the oldest instance , which is contrary to the design
VMware Cloud Director Availability 4.7.X
Storage performance issue could be found in VI environment
Contact to storage vendor for further investigation