Comment 9 for bug 1699660

This is still a problem in 18.04. Like the OP, I have localhosts on my LAN, but have no local domain configured. I had to disable systemd-resolved on each of my LXC containers. What's worse, resolvconf creates an empty /etc/resolv.conf file. So I had to create resolv.conf by hand and point to DNS. Again, on each of my containers.

This is a major regression. If the systemd-resolved is to be kept, at least have some decency to explicitly note in 18.04 LTS release notes that local hostname resolution requires local domain to be configured for name resolution to work.