Unable to make a Global Manager as standby from the UI after an unplanned switchover where this Global Manager was lost but is back online after the switchover.

Products

• VMware NSX

Issue/Introduction

Symptoms:
Previously active Global Manager status is "NONE" in the UI after coming back online.
Unable to make old Active Global Manager as standby from the UI after unplanned switchover.

Environment

VMware NSX-T Data Center 3.x
VMware NSX-T Data Center

Resolution

This is ia known issue impacting VMware NSX-T for Data Center and is resolved in VMware NSX-T for Data Center 3.1.1 (Build Number 17483185) and above.

Workaround:
Use the following APIs with the payload including connection_info to change the status of the Global Manager from NONE to Standby:
 
1. GET https://<active-gm-ip>/global-manager/api/v1/global-infra/global-managers/<gm-id-to-be-changed-to-standby>

Confirm that the "mode" is set to "NONE" and note down the revision number at the bottom of the section in question.

2. PUT https://<active-gm-ip>/global-manager/api/v1/global-infra/global-managers/<gm-id-to-be-changed-to-standby>

API Body:

{
  "display_name": "GMLoc1",
  "mode": "STANDBY",
  "_revision" : <revision# from GET call above>,
 
  "connection_info": [
                {"fqdn": "<fqdn or IP of the GM with status NONE>",
                 "username": "<username>",
                 "password": "<password>",
                 "thumbprint": "<API thumbprint of the GM with status NONE>"}
  ]
}




Note: 
If GET API call in Step 1 returns an "object doesn't exist" then you must provide the revision -1 as if you are creating a new resource in Step 2.  For example: 
PUT https://<active-gm-ip>/global-manager/api/v1/global-infra/global-managers/<gm-id-to-be-changed-to-standby>

API Body:

{
  "display_name": "GMLoc1",
  "mode": "STANDBY",
  "_revision" : -1,
 
  "connection_info": [
                {"fqdn": "<fqdn or IP of the GM with status NONE>",
                 "username": "<username>",
                 "password": "<password>",
                 "thumbprint": "<API thumbprint of the GM with status NONE>"}
  ]
}

Additional Information

For GM Failover:
1.    If the failover from Standby to Active is a PLANNED failover: There are no additional steps needed once the failover is complete and roles should switch automatically in both GMs
2.    If the failover from Standby to Active is UNPLANNED failover (i.e. Active is down / unreachable):
        - Standby will take over as Active by force
        - In an unplanned case, this means that the old Active GM is no longer available. When it comes back up it is marked as NONE since the user might decide to use that GM as Standby, or use a new Standby GM. When a Standby GM needs to be added to the unplanned failover's Active GM we need to specify connection info (regardless of whether it's a new GM or existing GM)

Impact/Risks:
Using UI user will not be able to make old Active as standby after unplanned switchover.