If you have come to a point where you no longer need a specific Site to be included in your HCX+ inventory, you’ll find that the process to remove it is fairly easy.
You will start from the bottom of your configuration and work your way up. If you have any VMs that live on networks that have been extended from the Site to be removed, you’ll want to get them to some other network. Then you will remove any network extensions, followed by removing the Site Pair, and lastly you’ll remove the Site.
Navigate to Services > Network Extensions.
If you click the three vertical dots next to any extended network, you will get a menu that will give you the option to Unextend Network.
Click Unextend Network.
Our documentation describes best what leaving the “Connect the cloud network to the cloud gateway after un-extending” option checked will do.
Selecting this check box connects the cloud network to the cloud edge gateway after removing the extension. If dynamic routing is activated, the cloud network is advertised from the cloud Edge Gateway and might cause a routing conflict.
https://docs.vmware.com/en/VMware-HCX+/services/Using-Managing-HCXPlus/GUID-48BC3025-5612-4EC8-B15B-47DCDCC08646.html
There are no VMs on any of the Network Extensions at the Cloud site (Cork) so leaving this checked is not a concern in my example.
Click the Unextend button.
You will see that the previous network is no longer extended.
Repeat the Unextend Network operation for other extended networks created under the Site Pair that needs to be deleted (all of them in this example).
You should be able to see that there are no Network Extensions in the HSM UI as well.
The segments created at the destination site NSX installation that facilitate these extended networks are left behind but can be cleaned up manually if necessary.
With the Network Extensions removed, you should be able to remove the Site Pair now.
Navigate to Infrastructure > Site Pairs and click the Actions dropdown to see the Delete action item.
Click the Delete link.
Click the Delete button.
You can click the View Details link for the Site Pair to see specific tasks that are being done to remove the Site Pair.
Click on the Activity Logs tab.
In the vSphere Client, you will see the IX and NE VMs being deleted.
Eventually, you will see all tasks for the Site Pair move to a completed state.
And the Site Pair will be removed.
The same is seen in the HSM UI.
The Profiles and Service Mesh are also removed.
You should finally be able to remove the desired Site now.
Navigate to Infrastructure > Sites and click on the Actions dropdown under site to be removed (Cork in this example) to see the Deregister Site action item.
Click the Deregister Site link. Type the name of the Site to be removed (Cork).
Click the Deregister Site button.
You should see the Site removed from the list of Sites.
In the HSM UI for the site that was removed (Cork), you can see that the banner noting that the Site is managed by HCX+ is gone.
Note that there is still historical information about migrations that occurred.
You can continue removing Sites until none are left if desired.
The very last thing to do would be to power off and delete the HSM VM deployed at any deregistered sites and then remove the HCX extension from the associated vCenter Server. You can find instructions for doing this in Cannot remove or disable unwanted plug-ins from vCenter Server and vCenter Server Appliance (1025360). The extensions to look for are com.vmware.hcx.plugin and com.vmware.hcsp.alarm.