Arvados

In order to avoid requiring a more complicated split-horizon DNS setup, the salt installer takes the internal IP addresses of the services and updates /etc/hosts so that internal services use the internal IP and not the external IP. However, this is not documented and it is confusing.

The installer docs should say something about this behavior.

If the user makes an error in the IP addresses list, it'll fail in a confusing way because it uses the local /etc/hosts. However, if they update local.params it doesn't update /etc/hosts before trying to contact nodes (which have the wrong IP address in /etc/hosts).