On Fri, 25 Jan 2002 18:46:55 PST, Simon Higgs <simon@higgs.com> said:

Can someone explain this trace to me. How on earth did the 10.0.0.0 network get inserted into the last hop?

# IP address Host name Round trip time

4 24.130.2.243 GSR1-SRP4-0.lsanhe4.we.mediaone.net 64 ms 5 24.130.2.242 GSR2-SRP4-0.lsanhe3.we.mediaone.net 71 ms 6 12.125.98.13 Unavailable 79 ms 7 12.123.28.94 gbr2-p100.la2ca.ip.att.net 94 ms 8 No response 9 12.122.11.226 ggr1-p340.la2ca.ip.att.net 110 ms 10 192.205.32.246 att-gw.la.home.net 112 ms 11 24.7.74.182 wbb1-pos2-0.pop1.ca.home.net 120 ms 12 10.252.25.118 Unavailable 134 ms 13 209.125.128.80 Unavailable 141 ms

Some naughty person used RFC1918 address space to number their point-to-point links? That's OK, until they throw an ICMP error that gets tossed by a border router that does bogon filtering. Single biggest reason why Path MTU Discovery doesn't work, except for maybe sites that stomp on all the ICMP traffic they see.... -- Valdis Kletnieks Computer Systems Senior Engineer Virginia Tech