This article provides recovery steps for a scenario where 2 of the 3 NSX Managers are lost or are no longer functional.
VMware NSX
A 3 node NSX Manager cluster will continue to be fully functional if 1 node is lost.
When 2 nodes are lost, the cluster will no longer be operational as the majority has been lost.
With only 1 node remaining, it is no longer possible to login to the UI.
The official and supported procedure to recover the NSX node cluster is to deploy a new appliance, restore from backup and then add two additional nodes.
In the event that a restore from backup is not possible, there is a small possibility Broadcom Support may be able to recover the cluster.
To have the situation assessed please open a support case referencing this KB, for more information, see Creating and managing Broadcom support cases.