Routers have multiple addresses, typically at least 3 if not more: one facing end users, one facing upstream and a loop back address. Some network operators choose to use a loop back address for traffic replies in things such as traceroutes. Especially as some may be using rfc1918 addresses on some interfaces. -------- Original message --------From: Jon Schewe <jpschewe at mtu.net> Date: 9/3/17 7:47 AM (GMT-06:00) To: TCLUG Mailing List <tclug-list at mn-linux.org> Subject: [tclug-list] Odd networking on Comcast I'm trying to debug some issues with my internet connection. I have Comcast and the traceroute results are not coming back what I expect. On my router my routing table looks like this: >netstat -rnKernel IP routing tableDestination Gateway Genmask Flags MSS Window irtt Iface0.0.0.0 73.37.164.1 0.0.0.0 UG 0 0 0 enp1s1073.37.164.0 0.0.0.0 255.255.254.0 U 0 0 0 enp1s10 Given that, I expect the first hop in a traceroute to be 73.37.164.1, but it's not.>traceroute -n 8.8.8.8traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets 1 96.120.48.69 8.890 ms 14.915 ms 15.659 ms 2 68.85.168.121 14.833 ms 15.604 ms 15.575 ms 3 96.108.188.62 14.502 ms 14.484 ms 14.665 ms 4 96.108.188.101 15.455 ms 16.596 ms 16.574 ms 5 68.86.94.81 28.011 ms 26.859 ms 26.841 ms 6 68.86.85.158 24.289 ms 19.757 ms 22.386 ms... Can anyone explain what's going on here? - Jon -- http://mtu.net/~jpschewe -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mailman.mn-linux.org/pipermail/tclug-list/attachments/20170903/4319c542/attachment.html>