I have a firewall text file, in which every time my system starts up I copy the firewall text, then past it into the root terminal. Then, I am happily protected by a firewall!

The only problem is that I would not like to do this. I would rather have my firewall start via a startup script automatically. So, can I just edit some file and paste my startup script in there? What exactly should I do?

I would rather have my firewall start via a startup script automatically. So, can I just edit some file and paste my startup script in there? What exactly should I do?
On RH*L(-alike) systems, if the iptables package is installed you should have
- an initscript which should be set to run in the runlevels you boot into: check with "chkconfig --list iptables" and your current runlevel is displayed by running "runlevel". If chkconfig doesn't show it to run in the runlevel you're in, run "chkconfig --level LEVEL iptables on" where LEVEL is/are the runlevels it should be on in. If you need it for multiple ones don't use spaces but use "--level 2345".
- a service configuration script /etc/sysconfig/iptables-config which should show options like IPTABLES_SAVE_ON_STOP= and IPTABLES_SAVE_ON_RESTART=. If the script you're running manually is mature enough and you don't want any changes set these options to "no".
- an iptables rules file /etc/sysconfig/iptables. Run your script manually and issue "/sbin/iptables-save > /etc/sysconfig/iptables" which will populate the rules file. You can check it out to see how your rules are saved and edit it if necessary.

Now all is set. Since you manually entered your rules you should not need to restart the firewall. Run "/etc/rc.d/init.d/iptables status" or "service iptables status" or "/sbin/iptables -n -L -v" to check all rules are loaded. On reboot all your rules should be loaded automagically.

The default SuSE install has an excellent operating firewall. YaST configuration of services automatically updates the firewall. There's a command line utility available called nmap that will tell you which ports are open by trial and error.