If you use
$ ps -ef
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
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.