If upgrading from <v15.10.0:
To upgrade to this version, follow the instructions in the OPTIONAL UPGRADES section of local_setup_instructions.sh.
If you do not follow the upgrade instructions BEFORE trying to run this version, you will get the following error:
ActiveRecord::ConnectionNotEstablished
could not translate host name "db" to address: Temporary failure in name resolution
At which point you will need to revert to the previous version and then follow the upgrade instructions.