How to enable Firebird to work through network protocol at CentOS 6.x

To enable Firebird to listen to the external requests at CentOS 6.x (ip_address:/path/database.fdb), add to the file /etc/ sysconfig / iptables the following line:

-A INPUT -m state --state NEW -m tcp -p tcp -- dport 3050 -j ACCEPT

Then run

/etc/init.d/ iptables restart

Check the result with commands

netstat - tulpn | less

iptables -L -n

If you are using events, set RemoteAuxPort parameter to some explicit value and add it to iptables too.