Laurie Brown wrote:
The replacement (and enhancement) for ipchains is iptables, which is only supported in the 2.4 kernel or later.
Thanks for the pointer Laurie. Unfortunately my Linux text books are a little out of date and although saying a bit about ipchains do not mention iptables at all.
As usual, Linux >2.4 also supports ipchains, *but* the two can't run on the same box at the same time. It may be that you have iptables already installed. Try typing "iptables -L" and see what happens.
"iptables -L" works so, as you suspected, it appears I must have unknowingly installed iptables when I installed Linux. It is simply that I did not know it existed. I notice that you mention that the two programs cannot coexist... that probably explains why I could not get ipchains to work.
... One of the many advantages of the SuSE distro is that it comes with an easy-to-use tool called personal-firewall which is designed for just the scenario you describe. That said, a few hours reading on the net, and some fiddling about will produce a working firewall script which you can call from your ipup script.
Thanks to your help Laurie, now that I know what I am looking for, I have indeed found an easy graphical interface. I must admit however that I like experimenting with things (I guess that is what is drawing me to Linux in the first place) so although I will probably use the graphical interface produced rules as a starting point I would like to experiment with them so as to try to learn what they are doing (though will make sure I back up the original config file first as, knowing me, I will soon render my system unusable!).
Thanks for your help.
Ian.