Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!OMNIGATE.CLARKSON.EDU!bkc
From: bkc@OMNIGATE.CLARKSON.EDU (Brad Clements)
Newsgroups: comp.protocols.tcp-ip.ibmpc
Subject: Hacking CMU sources to TurboC
Message-ID: <8805271627.aa21337@Louie.UDEL.EDU>
Date: 27 May 88 20:24:23 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 54

Hi,

I'm converting the CMU sources to TurboC 1.5. If anyone has already done this
and has it working, please tell me so I can stop banging my head against the wall.
Otherwise, those of you who have messed around with the source would you please
think about the following problem and perhaps offer a suggested solution.

Facts:
	Interface NI5010
	TurboC version of Netwatch works fine.

	Trying to get ping to work, ping -s enters server mode, accepts
	ICMP ping requests from host A. Ping looks up the ip address
	in its tables (which are empty) and since it doesn't find the 
	IP address it sends out an ARP REQ broadcast. Host A sees the 
	ARP REQ broadcast and sends an ARP REP which ping NEVER sees.

	Meanwhile, ping does see lotsa ARP REQs from other hosts, none directed
	at it so those are not placed in its tables.

	Other broadcasts are seen, such as IP/UDP broadcasts, and dumped
	by ping.

	Now, here's the crazy part, I removed the ARP table entry from host A
	for the ping PC. I placed ping in server mode, then tried to
	ping it from host A. That worked. Apparently ping gets
	the ARP REQ sent by host A and saves host A's ethernet/ip address
	since it will probably need to reply to it in the future. 


Since ICMP echo requests are not broadcasts, the interlan driver is receiving 
some packets, but not ARP REP. 
Except that netwatch correctly shows ARP REQs and REPs but I think thats because 
the NI5010 is set to receive ALL packets, broadcast or otherwise.

Can anyone offer an idea as to where to look for the missing packets.
Ping does not report:
	a. packet too short
	b. unkown packet type (either ping or Arp types)

On a quiet subnet, I set ping to single shot ping host A. Using LanWatch (thanks FTP!),
there was exactly one ARP REQ sent by the ping PC and one ARP REP returned. 
However the ping program exited and stated:

1 packet sent
0 packets received.

This is driving me crazy, if anyone has any ideas I'd appreciate them.

Thanks,
Brad Clements
Network Engineer
Clarkson University