I had installed onlyoffice document server on my ubuntu 14.04 machine but after I restarted the server all the applications of onlyoffice shutdown and I am not able to restart them. It currently shows 502 gateway error.
Possible reason - problem with supervisor, but that problem was on Ubuntu 16.04 with systemd
It was solved via
# Make sure Supervisor comes up after a reboot.
sudo systemctl enable supervisor
# Bring Supervisor up right now.
sudo systemctl start supervisor