I’ve deployed 3 NSX Managers individually from the NSX OVA onto a single vCenter. By having 3 individual Managers, I have the option to create multiple clusters from each one (probably excessive and incorrect in my case). Instead my goal is to join all 3 individual managers to form a 3-node cluster and then assign a VIP.
For this process, I will be following VMware documentation that is provided here: Form an NSX Manager Cluster Using the CLI
My 3 NSX managers I will be referencing and joining are nsxcon1, nsxcon2 & nsxcon3
Here is an example of nsxcon1 UI reviewing the ‘Appliances’ section, you can see there is only a single appliance and an additional one cannot be added until a ‘Compute Manager’ (such as a vCenter) can be added.

I did verify CLI connectivity to each of the appliances by running
get cluster status
This command will return cluster health for the NSX Manager and any appliances that are part of the cluster, for this example, it’s only a single appliance

From the first NSX controller you will want to obtain the thumbprint by
get certificate api thumbprint
That will provide you the thumbprint of the targeted appliance

Moving onto the other node (nsxcon2) which we want to join to nsxcon1, we will use the following command
mgr-new> join <Manager-IP> cluster-id <cluster-id> username <Manager-username> password <Manager-password> thumbprint <Manager-thumbprint>
Here is an example of what it looks like when populated in that command and ran from the node we want to join to our primary one.

*Please ensure you have taken appropriate backups as this will take this node and try and join it to another cluster, being this should be a vanilla install, should not be too much to have to re-deploy.
After a couple of minutes we do receive the following prompt

We can then go back to nsxcon1 and verify with ‘ get cluster status’ and see that the cluster status is ‘DEGRADED’ however this is normal while the node is completing it’s process with joining and updating the embedded database.

We can take our ‘join’ command earlier we used on nsxcon2 and then run it on nsxcon3 again.
After running it, going back to nsxcon1 and checking cluster status..we now have 3 appearing

After a few minutes, our GUI has been fully populated with all NSX Managers reporting as stable

As a cherry on top, we will click on ‘Set Virtual IP’ and assign a dedicated IP address which also has it’s down DNS record.

There is our new virtual IP which has been assigned to one of the nodes
