IPFW disconnections and resets

[Siddhartha Jain]

Michael Scheidell wrote:
>>I use that all the time, maybe 1 out of 100 times it will kill 
>>a ssh session (only one that has irssi open cause of the time 
>>updating it kills it, i have it set to update every second 
>>though, so normally it'd be like 1 out of 500 or so) and even 
>>if it does, it still finishes loading the ruleset anyway so 
>>you can just ssh straight back in
> 
> 
> I used 
> 
> sysctl -a net.inet.ip.fw.enable=0  && firewall.sh &&
> net.inet.ip.fw.enable=1 && sleep 60 && reboot
> and I would hit a ^c to stop the sleep and reboot if I didn't wack the
> firewall rules.
>   The reboot would put it back to rc.conf firewall
> 
> Never got disconnected.
> 

Just out of curiosity, why is that IPFW behaves this way and PF and IPF
don't?

- Siddhartha