While booting a new node (octoprint), the entries in /etc/hosts matches the default installation, regardless how I edit things.
root@octoprint:/opt/octoprint/scripts# cat /etc/hosts
127.0.0.1 localhost
::1 localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
# Following entries are specific to your environment
10.255.12.51 einstein.thebikeshed.io einstein
Should be octoprint in this case.