If you have removed a Nexus 1000v VSM from vCenter without first removing it as a DVS, then you have an orphaned 1000v. The 1000v installation process creates a new folder with objects in the networking inventory of vCenter. You cannot remove this folder directly. You must install a new VSM and register it with the name of the orphaned 1000v (unless you want to try modifying the database directly which isn't recommended).
This blog assumes that the reader has some prior knowledge of the 1000v. Knowledge of how to connect with SVS and add the plug-in into vCenter is a must. I took information from various sources and came up with a process that worked for me.
I've created a 1000v with the hostname of 'switch' and the VSM is named 'Nexus1000v-orphan'
I then powered off the Nexus1000v-orphan VM guest and did a delete from disk in vCenter. So now I'm left with a folder called 'switch' than can't be deleted.
So now we need to create a new 1000v and register it to vCenter. Use a different hostname for now. Ensure that you register it to vCenter (svs connection 'connect').
Next we need to remove this new 1000v DVS from vCenter. Otherwise, we would end up with another orphan. Under the svs connection vcenter, do a 'no vmware dvs'
Now we need to remove both of the extension-keys used by these two 1000v's. First we need to find the keys and copy them to notepad. For the old orphaned 1000v, use vCenter and go to the networking inventory and view the summary, annotations.
For the new 1000v, do a show vmware vc extension-key.
Now we'll use the Managed Object Browser in vCenter. The URL is:
https://<IP of vcenter>/mob
Go to 'content' then find 'ExtensionManager'
The choose 'UnregisterExtension' and paste each of the two keys one by one into the value box. The browser should return a 'void' result if successful.
Now we need to change the hostname of the 1000v to match that of the orphaned 1000v. Then disconnect the 1000v from vCenter by doing a 'no connect' from SVS. Now change the extension-key to be the one form the orphaned 1000v by doing a 'vmware vc extension-key xxxx'.
Save the configuration and reload the VSM. Logout then back into vCenter.
Now we need to register the 1000v back into vCenter. Browse to the URL of the VSM and save the xml file. Add it as a plug-in into vCenter.
Now we need to connect the 1000v to vCenter. You may need to enter the data center name again (I've always had to). Note the switch exists in vCenter 'switch' and that the SVS shows a connection.
Now it's just a 'no vmware dvs' from the SVS on the switch. Note that the switch folder and all of the related objects have been removed from vCenter.
