Issue with DNS in container

[catfish]

I found 3 related posts.
permission error:

Apt can't resolve DNS on a LXC debian bullseye container

Thank you for your help, it was the starting point of a few-hours long investigation. I managed to solve the problem: somehow the /etc directory had permissions rwxr-x— and, of course, needed rwxr-xr-x. An apt sub-process that did not have root privileges could not read /etc/resolv.conf, thus the error I kept getting.

iptables SNAT:

[SOLVED] - No DNS access on LCX container

systemd-resolved conflict with ifupdown:

Problem with DNS resolution within a container

linux mint is based on ubuntu, so I guess third post may be your solution.