How do I find the IP addresses assigned to devices connected via Internet Sharing on Snow Leopard? Possible Duplicate:
  Show Active Connections to “Internet Sharing”  




Using the following scenario as an example:

I have a Macbook Pro connected to my LAN via its Airport.
I enabled Internet Sharing so that the Airport connection would be shared among any devices connected to the ethernet port of the MBP.
I plug a Raspberry Pi into the ethernet port of my MBP and boot it up.

How do I determine its IP address so I know what to SSH into?
Try pinging the broadcast address. This should work as long as the Pi got an IP from DHCP and responds to ping.

First, open up a terminal and run ifconfig en0. This should give you the info for your ethernet interface, if not, just use ifconfig and find it yourself. Make a note of the broadcast address. In my case, it's 192.168.2.255:

inet 192.168.2.99 netmask 0xffffff00 broadcast 192.168.2.255


So I'll run the command ping 192.168.2.255. Do the same with your broadcast address, and hit CTRL-C to stop the ping once you have some results:

Miramar:~ gabriel$ ping 192.168.2.255
PING 192.168.2.255 (192.168.2.255): 56 data bytes
64 bytes from 192.168.2.99: icmp_seq=0 ttl=64 time=0.113 ms
64 bytes from 192.168.2.1: icmp_seq=0 ttl=255 time=3.567 ms
64 bytes from 192.168.2.99: icmp_seq=1 ttl=64 time=0.096 ms
64 bytes from 192.168.2.1: icmp_seq=1 ttl=255 time=3.455 ms
^C


The broadcast is intended to go out to everything on the network. Everything that hears it should respond. In my case, I only see my IP and my router's - I guess it didn't bother passing the request on to my other machines, but you're directly connected to the Pi so you should see it there.