[Discuss] System receiving incorrect IP address

[epp at mcom.com (epp at mcom.com)]

Next problem...  :(

The other desktop (I'll call it Desktop 2.) is not receiving the correct
IP address. It, along with Desktop 1 were connected to a T-Mobile/ASUS
router that was being used as a switch. Desktop 1 and WiFi-connected
phone, correctly went through the router/switch and received an IP
address from the gateway. 

Note that both desktops are now connected directly to the gateway,
with all equipment having been power-cycled.

Desktop 1 continues to receive the IP from the gateway, yet Desktop 2's
network connection information continues to display an IPv4 address that
would have been assigned from the router, had it been used as a router,
but is apparently displaying an IPv6 address from the gateway. The
router's IPv4 address was set to use a different subnet and when I set
it up to use it as a switch, it's DHCP was turned off.

Where Desktop 2 is now connected directly to the gateway, it should
receive an IP from that and it's not. Yet, in the gateway, rather than
it displaying the hostname of the desktop, it displayed its MAC address
instead.

Is there a way of releasing/deleting the IP address(es) stored on
Desktop 2, so I can get a working IP? (Fedora Linux)

What I have tried so far, without success:

* dhclient -r
* ip addr flush dev <device name>
* dhclient <device name>
* assigned an IP address in the gateway
* repeated reboots of system

Thanks in advance.