Outline VPN Server doesn't work after installation

I would like to share with you a solution of one issue of the Outline VPN server. It might be useful for newbies in Linux and Docker. Hope this helps someone.

The issue

After successful installation of Outline VPN server it goes down (Outline Manager can't connect to the server).

Investigation

First of all, let's check the status of the docker containers (watchtower and shadowbox).

sudo docker ps

And there we see the issue - shadowbox container constantly restarting. Then we need to understand the cause.

docker logs --tail 50 --follow --timestamps shadowbox

And in the logs we notice the error "Error: getaddrinfo EAI_AGAIN localhost".

The solution

I found the solution there - https://github.com/Jigsaw-Code/outline-server/issues/1131

Everything that you need is add new line "127.0.0.1 localhost" into the "/etc/hosts" file on the server.

After next attempt of restarting the shadowbox container continue stable work. Happy end.