Simphony, cannot reload database from behind firewall

[forbino]

So if I move the server outside the firewall, reloading the DB works fine. From inside the firewall the following error pops, after a surprisingly long time. Looking for anything obvious I'm missing. Haven't even been able to find a reference to this error from oracle.

 

[Niko S]

Did you open the ports in the firewall rules?

 

[virat321]

Close service host
increase tcp global max syn retransmission to maximum value
restart the service host and try