No, it's not a Sun issue, it drops every other packet only if I got over the ATM Backbone. I can trace to another router, a ATM Switch, A CSU panel, anything and I get the same dropped packet. I did further testing, and it is every other packet, not just the middle one. Eric At 05:11 PM 9/27/96 -0700, maillists wrote:

...

hmm.. Seems that every traceroute across an ATM link will result in the middle packet being dropped. The ATM Switch nor the Router have any idea that it is the second packet.. weird! Anyone have a clue to why that is?

Tracing the route to ns2 1 206.222.97.6 44msec 44msec 44msec 2 ns2.acsi.net (206.222.97.50) 44 msec * 44 msec

I don't think it has got anything to do with ATM. I bet you that ns2.acsi.net is a Solaris 2 box. Solaris drops every other icmp echo if it comes too close to the last one. This I was told is an inadvertent bug although Sun could claim it to be a feature against an ICMP flood attack ;-)

Try tracerouting to sun.com (a SunOS box) and playground.sun.com (Solaris 2). You'll see the difference. Also try traceroute with the -q parameter greater than the default of 3 packets each destination.

Sanjay.

--------------------------------------------------------------- Web Professionals, Inc. 20370 Town Center Lane, Suite 245 +1 408-865-0899 Cupertino CA 95014 USA http://web.professionals.com --------------------------------------------------------------- World's largest Webspace provider with dedicated domain sites Ref: Open Market's Commercial Sites Index www.directory.net --