I know this is a bit off-topic, but meet on grommunio won't always work well.
That's not Grommunio related, but rather a desgin by jitsi.
When jitsi shares https 443 port via a reverse proxy with other apps, the UDP traffic can't work, so some conferences will be dead slow and will use tcp.
This will only happen when the end user is behind a firewall that filters output to udp ports 10000-20000, typically enterprise setups.
The only good solution I've found is to setup a separate jitsi server with his own IP.
Even then jitsi themselves recommend setting up a second JVB bridge which listens un 443 tcp and udp on another IP, making the investment for a full blown solution 2 servers with 2 public IPs.
Currently haproxy 3+ supports UDP protocols, and perhaps nginx does too, so there could be ways to make it work, but AFAIK, this isn't implemented as of today neither in jitsi nor in grommunio setups.
