Networking help

[pll at lanminds.com]

In a message dated: Mon, 25 Nov 2002 16:10:41 EST
"Ken D'Ambrosio" said:

>I shouldn't be an ARP issue -- if it were, then the other machine sending
>pings wouldn't work.  Namely:

Keep in mind.  The pinging machine, systemA *cannot* ping systemC, 
but *can* ping systemB.  B and C are on the same subnet, A is not.

By 'cannot ping' I mean, I type 'ping systemC' and it just sits there.

However, by ssh'ing to systemB, and from there to systemC, I run
'tcpdump -i eth1 icmp' and I can see that systemC *is* in fact 
receiving the "icmp echo request" packets.  systemC just isn't 
replying to them!

>I do, however, have to wonder if you're routing correctly.
>Can you ping the remote subnet's router address?

Yes, from all systems!

> Is there any chance that the remote machine's got a static route with
>an incorrect subnet mask?

No.

>Can you swap IP addresses with the machine that works and give that a go?

Maybe, but as I technically have several "systemC"s I know it's not 
limited to this one system.

Here's tcpdump output from systemC, the system which I *cannot* ping 
from my system.  There were 38 packets sent by my system, but it 
wasn't until the 31st packet that this system decided to respond.

     15:23:38.618442 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:39.618222 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:40.618071 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:41.617916 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:42.617833 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:43.617638 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:44.617467 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:45.617314 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:46.617203 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:47.617007 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:48.616901 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:49.616736 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:50.616602 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:51.616469 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:52.616281 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:53.616185 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:54.615980 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:55.615844 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:56.615685 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:57.615534 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:58.615416 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:23:59.615264 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:00.615092 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:01.614943 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:02.614784 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:03.614696 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:04.614558 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:05.614353 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:06.614212 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:07.614047 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:08.613903 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:08.613945 www-eth1 > 168.159.36.66: icmp: echo reply
     15:24:09.613768 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:09.613787 www-eth1 > 168.159.36.66: icmp: echo reply
     15:24:10.613646 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:10.613658 www-eth1 > 168.159.36.66: icmp: echo reply
     15:24:11.613466 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:11.613499 www-eth1 > 168.159.36.66: icmp: echo reply
     15:24:12.613447 168.159.36.66 > www-eth1: icmp: echo request (DF)
     15:24:12.613472 www-eth1 > 168.159.36.66: icmp: echo reply


-- 

Seeya,
Paul
--
	It may look like I'm just sitting here doing nothing,
   but I'm really actively waiting for all my problems to go away.

	 If you're not having fun, you're not doing it right!