Docker currently bind-mounts to the container's /etc/resolv.conf. This causes problems when installing utilities such as resolvconf/dnsmasq/dhcpd, because /etc/resolv.conf needs to overwritable. Here's the output when trying to run resolvconf:

lsattr: Inappropriate ioctl for device While reading flags on /etc/resolv.conf
ln: cannot remove `/etc/resolv.conf: Device or resource busy

However, /etc/resolv.conf is a sensible default location. Can we instead make the mount location configurable?