Unknown IPFW log message

[Dan Nelson]

In the last episode (Apr 28), Jerry said:
> In the security.log, I have been noticing the following:
> 
> Apr 28 12:04:20 scorpio kernel: ipfw: 4400 Deny P:2 192.168.1.1 224.0.0.1 in via nfe0
> 
> I have not been able to document what the "P:2" stands for. Neither, have
> I been able to find out if I should continue to allow the block to
> continue.  Googling has turned up a few posts that seem to indicate that I
> should allow it.

Since "P:2" is where either "tcp" or "udp" would be, it's probably the
protocol number.  /etc/protocols says 

igmp    2       IGMP            # internet group management protocol

I don't know what igmp is used for, though.

-- 
	Dan Nelson
	dnelson at allantgroup.com