I do appreciate that y'all are still helping me with this.
I have reached out to the network team to see if they can help track this down. When I look in the properties of the client in the Host Properties\Clients section - it reports the IP of the server. I've checked DNS and Vsphere. In both cases that IP is assiated with the current Windows u1probob01v server.
I'm pretty familiar with NBU on linux, but not so much Windows. Where is the client configured on the windows box? I've looked at the Backup, Archive, and Restore utility - (couldn't find anything in there that says Linux) - is there some other client utility on the server that retains NBU information that might have bad information in it?
While I was typing the above - Net-ops has come back and said they don't see any issues that could be causing my problem. (so no IP issues) I'll see if I can dig deeper on the vmware side -
Try compare MAC addresses ?
On master and media, get the MAC of the client from :
...and compare that to MAC address of the client in VMware ?
this remained a problem until I updated to NBU 8.2 (linux) - then the server showed up in the Host Properties/Clients as a Windows server