Budgie2

Originally Posted by hcvv

I am with @avidjaar that you probably should do less of prose, but more a step wise explanation of what you do..

But it is possible that I more or less understand what you mean.

1. You configure NM with a fixed IP address, thus telling it explicitly that you do not want it to use DHCP to get an IP address from any source.
2. You disconnect the ethernet cable and connect it to another network.
3. NM still tries to use the IP you told it to use and that fails of course because there is no partner within the subnet now connected.

IMHO this is a logical situation. I do not know of any way how NM can decide that your configuration all of a sudden should be changed from not using DHCP into using it. NM fails the feature of mind reading.

I understand and my explanation is not clear.

A simple example is when I have wifi turned off and I am using NM to select one of several connections each of which I have configured with automatic connections not enabled and then saved in advance.

This is for the purpose of selecting devices which have known but differing default IPs when there is no DHCP server.

The connections are not shown for me to select unless a network connection is plugged in and eventually no lan connections are shown as available for selection. This is true even if I disable and then enable the box described as "Enable mobile network" in the pop-up from my task bar.

No mind reading required, I just to be able to control the connection. If it doesn't work it is my problem not NM doing the thinking for me.