what port is tomcat 6 running on

If you use

$ ps -ef

or

$ top

you should be able to find the PID (Process ID) for your opengeo-suite.

With the PID in hand, you can use netstat and grep to find out what port it's running on. For example, I can see the PID of my tomcat is 1483. So using,

$ sudo netstat -lnp | grep 1483

I get the result:

tcp6       0      0 :::8080                 :::*                    LISTEN      1483/java       
tcp6       0      0 127.0.0.1:8005          :::*                    LISTEN      1483/java 

I don't think you asked this, but for completeness, to find the process ID when you know port number:

$ sudo lsof -i:8080 -n

gives

COMMAND  PID    USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
java    1483 tomcat6   36u  IPv6   3496      0t0  TCP *:http-alt (LISTEN)

Note, netstat and lsof will run without sudo, but they won't show all ports. In my case, sudo was necessary to see the tomcat ports.

Try the below:

netstat -ntpl | grep java
tcp        0      0 127.0.0.1:**8005**          0.0.0.0:*               LISTEN      2710/java
tcp        0      0 0.0.0.0:**8008**            0.0.0.0:*               LISTEN      2710/java
tcp        0      0 0.0.0.0:**8009**            0.0.0.0:*               LISTEN      2710/java

By default it runs on port 8080

You can scan your ports and other's ports by using "nmap"

For your own machine:

nmap localhost