Bridge Adapter (NAT IP disappears after some time)

[tomaas]

Hello, I have Bridge Adapter with wlan0 name, promiscuous mode: Deny (the default config in network attached to: Bridged Adapter) in Ubuntu Server guest. When I boot the guest, the router SELF ASSIGNS (not DHCP) two different NAT IPs. This is exactly what I want, as I can point my guest Ubuntu to be a web-server.
The problem is that, after some time (1h, 6h,... hours) those self assigned IPs get released and my host computer gets assigned an IP with DHCP. So my web-server in the guest looses NAT ip, becomes unreachable with no internet in guest.
I have no idea why is that happening :/
I would appreciate any help.

[LinuxPalatina]

Hi,
why you arrange the addresses to non-fixed (via MAC Address) ?