Fresh Gui install. Two nics on different networks. If I enable one with
network manager in gnome, it disables the other one. Re-enable the one
it disabled, and it disables the other one??
Turns out this was a graphical install that created file called
ens3.nmconnection in /etc/NetworkManager/system-connections. I removed
this file and rebooted. Both nics can now be enabled at the same time.
A Text install creates a file called "Wired Connection 1" in the same
folder. Removed it to resolve.
Looks like these files get created if you install a graphical desktop
(gnome) during the install. Three different installs, same results.
I did a text install with no gui, then installed the gnome desktop
after reboot. No issues.
This is a virtual machine install running on an Ubuntu 18.04.1. Kernel
5.4.0-77-generic #86~18.04.2-Ubuntu SMP. 64 Gigs Ram.
qemu-kvm version 1:2.11_dfsg-1ubuntu7.37
Debian ISO debian-11.0.0-amd64-netinst.iso
size 395.3 MB
md5sum 499953266841cae41612310e65659456
sha256sum ae6d563d2444665316901fe7091059ac34b8f67ba30f9159f7cef7d2fdc5b
f8a
Installs:
Debian Gnu/linux 11 (bullseye) x86_64
kernel 5.10.0-8-amd64
shell: bash 5.1.4