A name resolution issue with systemd-resolved we found in the wild
As you may know, you can connect Moss to your fresh Ubuntu 18.04 or 16.04 server – regardless the provider where such server is hosted. Moss also features native integrations with some cloud providers (Amazon, DigitalOcean, Google and Vultr as of this writing), but you can use Moss with any vps, cloud instance, or even physical server – not a common use case, but feasible anyway.
A few days ago a customer was having an issue when trying to connect an Ubuntu 18.04 instance (hosted on his provider of choice) to Moss. So I decided to create an account on such provider and investigate the problem. It turned out that the provider’s image had some “suboptimal” configurations and that the default solution for name resolution in Ubuntu 18.04 (bionic) has some related bugs. I think the problem is interesting enough to be shared, and it’ll also allow us to talk about systemd and, more specifically, systemd-resolved for name resolution.