Traceroute losses through

Joel jaeggli joelja at
Sat Sep 17 20:21:40 UTC 2011

On 9/16/11 11:42 , Steve Bohrer wrote:
> My general question is "what meaning do I give to lossy traceroutes,
> even when pings show no problem."
> Can I expect that backbone routers should never give me timeouts on a
> traceroute through them, so, lots of asterisks from these systems
> indicate a packet loss problem that needs to be fixed?

generation of icmp exceptions e.g. ttl exceeded can/is delberately rate
limited, such traffic is sent up to the control plane. if a router is
passing traffic loss free through the forwarding plane then you can
conclude that it's loss free through the forwarding plane.

> Or, are these traceroute asterisks essentially meaningless, and should
> be expected on any busy link?

more like it's not trivial to conclude what they mean.

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