Iptables with other than standart ports

[Terrorkarotte]

I am having trouble setting up the iptables.
When I start a server with the -autoupdate option or try to update it by hand using the steam tool all i can see is:

Code:

Checking bootstrapper version ...

So the gs cant connect to the content Server.

I am using this rules for now. When I start the Server before adding the rules they keep on working. But a restart is not possible because of the above named problem.

Code:

iptables -A INPUT -p udp -m udp --dport 20000:20020 -j ACCEPT
iptables -A OUTPUT -p udp -m udp --dport 20000:20020 -j ACCEPT