manually fixing IPs

[Jon Masters]

Hello,

So, back in the good old days, one could just type this:

ifconfig eth0 some_temp_ip up

Then it became necessary to:

/etc/init.d/NetworkManager stop

Then it became necessary to:

systemctl disable NetworkManager.service

Just to try to get the interface left alone.

But when the link it's attached to drops, the settings are immediately
being dropped and the interface unconfigured. So, what have I missed?
What's the other thing that's trying to be all "helpful" but actually
preventing me from running TFTP usefully? Sure, I could plug it into a
switch and go all Windows 95 on this, but...I'd rather not.

Thanks,

Jon.