I have been restructuring my homelab quite a bit- mainly segregating certain virtual machines onto their own VLANs- and decided to tidy up IP allocation on VLAN0. This is already a sensitive subject for me. I’ve reallocated IP addresses within my vCenter cluster previously and had serious difficulties with permissions.
In theory, changing the IP address on an ESXi host should be simple and achievable through the vSphere Web Client but I was getting an error
An error occurred while communicating with the remote host. Network configuration change disconnected the host 'xxx.xxx.xxx.xxx' from vCenter server and has been rolled back
I could have shut down the server, connected a monitor and changed the IP through the ESXi console but what about dat uptime?
Per usual, VMware’s documentation was both vague and inaccurate, here’s, without too much overthinking into the how and why, a workaround.
Install the vSphere Client. To download, browse to the IP address of your ESXi host. There will be a link
Log in to the ESXi host
Shut down all virtual machines (backup all virtual machines too, which I absolutely definitely did and you should too)
Click the host address on the left, then navigate to the Configuration tab
Click Networking
At the vSwitch that contains Management Network select Properties
In the window, select Management Network then Edit
In the IP Settings tab, enter the desired IP address and hit OK
I got a warning about disconnection, the client became intermittently unresponsive then disconnected. Five minutes or so later, I was able to reconnect to the new IP address assigned above.