Recently I installed PlexMediaServer snap, and it wasn’t working because of failing DNS. After some digging and I noticed that in its chroot /etc/resolv.conf is linked to /run/resolvconf/resolv.conf, which didn’t exist in my box.
This was fixed with:
$ sudo apt install resolvconf
But it seems that since “Core” depends on resolvconf, there should be a dependency in “snapd” deb to “resolvconf” ?
My ubuntu installation is 19.04, but it has been upgraded for many years – as opposed to installed from scratch. So maybe that’s why resolvconf deb package wasn’t installed by default ?