I have installed Ubuntu server a lot of times, mostly versions prior to 20.04 obviously, but still.
I have done this exact thing in the past on earlier version (versions 16 and 18 most predominately with this exact setup) and never had issues.
20.04.3 breaks this and badly for some reason.
I have created a VM with two network interfaces, one on a DMZ with a static public internet IP address.
The second interface is on a private Class C network.
Using the installation wizard, I leave one interface in "DHCP" and the other I configure manually.
In previous iterations this would result in traffic over both interface - traffic going to the Class C network over it's interface and anything else going over the static interface.
It's been improved to the point it no longer works.
I can ssh in over the public static IP address with both interfaces up.
I can't ssh into the Class C interface (from the Class C network) at all.
that is until bring down the public interface - then it works with no issue.
Bring up the public interface and I lose access from the Class C.
If I down the public interface, ssh in on the Class C and then bring up the public interface, the session on the Class C address is immediately locked up.
Will creating two statically addressed interfaces make this work sanely again?
Side rant to vent some frustrations --
Seems like the best approach is simply go back to version 16 or 18 where networking is somewhat sane.
Who the heck came up with yaml cr@p for networking?
The different directory structures for configuration files and for the most part which file and in which order of precedence they are used is at best random -- will any give value replace a previous one or is this the magic one that concatenates with the previous one?
I want some of that drink -- that's some powerful stuff to make anyone think that's even remotely a good idea.
