how to make ESXi display with a short name instead of FQDN in vCenter

[RNAR]

I have a vSphere 6.5 vCenter Server appliance and both ESXi 6.5 and 5.5 machines. I want to change from having the FQDN displayed to having the short name / single label displayed in vCenter. This also affects how a machine must be referred to in PowerCLI. I know this can be done and has those effects because I've done it before to one of my 24 hosts. But, I can't remember at all how I did it. I have followed the instructions for versions up to 5.5 and that didn't work: disconnect host in vCenter, logon to it with vSphere client directly, delete the vpxuser account, connect in vCenter. The reason that doesn't work is that when I reconnect, the name is greyed out. I can't change it. I can only put in user name and password to connect it. And that all works fine. Another article from VMware said that whichever FQDN or short name appears first in the vCenter hosts file would be how it shows up. Well, that was again for up to version 5.5 with a Windows based vCenter instead of the VCSA. I added the machines to the hosts file. That didn't appear to do anything.

Does anyone know how to make this happen? I want to keep performance data; so, I don't want to completely delete the host and have to add it back to the cluster and the distributed virtual switch and all that.

[RNAR · Accepted solution]

I figured it out. The key was removing the ESXi host from the cluster. So, this worked with ESXi 5.5 on the vCSA 6.5: Modify the hosts file of the vCSA: enter all of the ESXi machines so that the short name is first, just after the IP address. Put a host into maintenance mode. Move it out of the cluster. Disconnect it. Connect directly to it with vSphere client or whatever and delete the vpxuser account. Go back to vCenter and connect. It will error out and you have to put the user ID and password in again. The name will still show with the fully qualified domain name and be greyed out in the dialog, but once that completes, it shows up in vCenter with the single label aka short name.

This also worked for my ESXi 6.5 machines, but I had a little extra trouble with them saying that some of the datastores already existed with the same name but a different backing file or something like that. I'm not sure why those machines had a problem and the others didn't. I ended up having to remove those hosts from the inventory and then add them back in which meant that I also had to add them back to the distributed virtual switch. So, not good, but I got everything fixed without too much trouble.