New to Ubuntu - Ethernet won't come up

[Robert Moskowitz]

I am new to Ubuntu.  Decades with Fedora and CentOS.  Only now needing 
to work with Ubuntu.

I am building a server to run Mail-in-a-Box which uses Ubuntu 22.04

https://mailinabox.email/

I have a Zotac Zboxnano that was sitting around with an old Centos7 
build.  I pulled the drive, put in an SSD card I had sitting around (had 
Fedora 24 on and not needed), downloaded the Ubuntu 22 ISO and 
successfully did the install.

I had no problem, that I saw, in accessing the Internet via the DHCP 
server on my AT&T router for the install.  I did not select to add any 
apps, because I don't know what I might want and Mail-in-a-Box setup 
says it will install everything needed.

So I reboot (pulled the USB DVD player) and watched the boot up.

The booting seemed to have a problem with network services?  Time out 
after something over 2min.

I logged in as me, and no network.  Using SUDO, I set root's password 
and su.

I played around with "ip addr add" and such and tried to bring up the 
interface but it stayed down.

I tried editing the yaml and use netplan without success.

I shot the day, sad to say.

Nothing in journalctl.  No indication anything has happened.  The lights 
are on the ethernet port, indicating data in and out?

But can't get the interface up.  It obviously was for the install and it 
worked fine with C7.

the netplan file has a dhcp4: true line; no dhcp6: line.  I know I have 
dhcp4 on that subnet.  Also public addr and I tried to hand config one 
of those.

Can I please have some pointers to try and figure this out?

thanks