How do I test that ports
(for example):

UDP 1200
UDP 27000 to 27015 inclusive
TCP 27030 to 27039 inclusive

are firewalled at the router?

How do I test this from behind the router?

It isn't recommended to do from behind the router for acurate results it would be better to ask a friend to run nmap on it.

You can go to Gibson Research and have the Shields Up tool scan you from the internet if that's what you are looking for.

Run nmap from a remote location! How? Go here!

You can even customise the nmap command.

nmap -sS -p 27000-27015 -PU Router-IP
nmap -sS -p 27030-27039 Router-IP

Won't this test the router itself?

I meant I need to test if I have the ability to use those ports.

I can't connect to IRC for example and I need to know if my administrator has firewalled it off.

Really I need to know what ports are available and how to use those port but I guess that could take ages.

nmap is still the answer.

nmap -sS -p 1200 -PU Router-IP #Test UDP 1200
nmap -sS -p 27000-27015 -PU Router-IP #Test UDP 27000 to 27015 inclusive
nmap -sS -p 27030-27039 Router-IP #Test TCP 27030 to 27039 inclusive

<edit> Of course you should replace Router-IP with the IP of whatever you are trying to connect to.

-bash-2.05b$ nmap -sS -p 27000-27015 -PU 127.0.0.1
Illegal Argument to -P, use -P0, -PI, -PB, -PM, -PP, -PT, or -PT80 (or whatever number you want for the TCP probe destination port)
QUITTING!
-bash-2.05b$

?

I don't want to scan what ports are open, I want to find out what ports are available from the internet to my server.

In other words, what services can I run on my server? It's no good nmap'ing myself as far as I can see because that only seems to pick up portas that are already running, which is no good; I already know port 80 is allowed.

One method I could try is to use netcat to opn aload of ports and then try to connect but I'm not too hot with scripting.

Also, I don't have root at the moment. I can ask for it if it's really needed.


Another way of putting it - I want to play Counterstrike, for example, and it's not connecting to port whatever. I need to be sure it's the firewall and not me.

Nmap is still the answer. Just go to Linux-Sec.net and they will run nmap against your IP.

How do u go to the ports to turn them on??? cause i now my firewall is blocking them

www.grc.net or the Sygate website and request a scan

Midget32, Welcome to LQ.

What distro are you using and which firewall?

Midget32, are you using portsentry or its likes? Look into the config files ... you will find entries that are instructing portsentry to restrict access. Once you comment them out, you should be fine.