Failed to install 'Database' role error

If you receive a 'Failed' notification or a 'An unknown error occurred, please try again later' error while installing the databse role, please check

1. Is your server behind NAT? If so, make sure "hairpin NAT" or "loopback NAT" is enabled. The server you are installing the database roel on needs to be able to reach its own public IP on port 50000.