What if you reduce clockrate and ping both local interface and remote
interface And measure the latency.
If the local ping takes twice the time as the remote ping then ....
Haakon Claassen
EMEA - IT Transport Services -WAN
Cisco Systems
De Kleetlaan 6b - Pegasus Park
B-1831 Diegem (Belgium)
-----Original Message-----
From: Marty Adkins [mailto:[EMAIL PROTECTED]]
Sent: donderdag 12 september 2002 6:19
To: [EMAIL PROTECTED]
Subject: Re: The Origin of Echos and Echo Replies [7:53148]
Priscilla Oppenheimer wrote:
>
> Interesting test. I think I understand it. ;-)
>
> Where are the debugs being run, by the way? The local router that is
pinging
> or the router at the other end? It looks like they are on the local
router
> doing the pings? Try running them on the other router. Be sure to turn
fast
> switching off on the other router.
>
> Regardless, what you are seeing makes sense considering this
(unbelievable
> but true ;-) discovery that pings to a local serial interface go out
across
> the serial link and bounce back from the router on the other end of
the
> link. So the subinterface on the other end of the link better be up,
eh?
>
Here's another interesting test with a point-to-point WAN link (or PVC).
Address the two ends as 10.0.0.1/24 and 10.0.0.2/24.
1) Ping the neighbor's IP -- typical echo & echo-reply. Note the RTT.
2) Ping the local serial IP -- packet is forwarded over to the neighbor,
which routes it back. Initiating router receives and replies to its own
ping. That reply is forwarded to the neighbor which forwards it back.
Double the normal round trip time.
3) Now the teaser... what happens if you ping 10.0.0.3?
Enable "debug ip icmp" on both routers and observe. :-)
- Marty
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=53193&t=53148
--------------------------------------------------
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
