I decided to upgrade to Ubuntu 16.04 form 14.04 on my pi 2, after doing a fresh install of Ubuntu 16.04 LTS ‘classic’ openfire has started crashing every few days.
Looked through the logs and i did not see any error messages on why it crashed.
raspberry pi 2
Ubuntu 16.04.2 LTS (GNU/Linux 4.4.0-1052-raspi2 armv7l)
Java Version 1.8.0_121 Oracle Corporation Java HotSpot™ Server VM
ARM/RaspberryPi - Ubuntu Wiki