You're getting SYN packets from the client (I assume these traces were
captured on the Mac), but no ACK reply. This means either :-
- the Mac doesn't want to respond (firewall), or
- the Mac doesn't know how to respond.
What's your routing table on the Mac?
> So, the requests get to the system but NOTHING appears in the logs in
> /var/log/httpd
No, the requests aren't getting to the box. You're only achieving the very
first part of the TCP handshake; to establish a connection you need to ACK
the incoming connection, SYN the outgoing connection, and get an ACK back
from the far end. This is usually seen as a SYN, SYN/ACK, ACK sequence.
You're not getting the SYN/ACK, so you're worlds away from getting any
HTTP over that connection...
> As can be seen from the first example, the request gets to the HTTPD
> server. IN the second, TCP seems to be blocking it.