how do I know my firewall is working

>
> Subject says it all! I used the CD from Linux mag. and installed pmfirewall.
> I see it starts on boot, but how do I know it's working correctly?
>
> pete

Find one of those sites that portscans you, and have them do it.
(search for 'security firewall' and 'port scan')

There are also a bunch of tools out there (look at rootprompt and
other such sites - search for security linux), but they have
the disadvantage that you rEALLY want to run them from
OUTSIDE your firewall, not ON your firewall or BEHIND
it...

if those pointers to search strings don't help, email me
back and I'll dig up my bookmarks (at work) and send
them along.