You have to open up the following ports for answering packages:
27950
27960
27965
27952
both TCP and UDP.
Worked for me at least, well now back to the game!
You have to open up the following ports for answering packages:
27950
27960
27965
27952
both TCP and UDP.
Worked for me at least, well now back to the game!
Why is your server firewalled? Plus, you can just open up whatever port you set the server to listen on. Ta-DA! 
Well it says so on the Activision’s customer support and when I opened those ports I could finally play.
Why is your server firewalled?
In my case, it’s company policy 
Anyway, my iptables setup looks like this (running on default port, 27960):
$IPTABLES -A $CHAIN -p udp --dst $ET_SERVER_IP --dport 27960 -j ACCEPT
$IPTABLES -A $CHAIN -p udp --dst $ET_SERVER_IP --dport 23000 -j ACCEPT
$IPTABLES -A $CHAIN -p udp --dport 27950 -j ACCEPT
$IPTABLES -A $CHAIN -p udp --dport 27900 -j ACCEPT
$IPTABLES -A $CHAIN -p udp --dport 27960 -j ACCEPT
I haven’t seen any problems with this setup, so I assume it covers everything that matters. If you know of something I missed, do tell.