Re: kern/52554: IPv6 connections not routing to default gateway

[Ryota Ozaki <ozaki-r%netbsd.org@localhost>]

On Fri, Sep 29, 2017 at 3:32 AM, Roy Bixler <rcbixler%nyx.net@localhost> wrote:
> On Fri, Sep 29, 2017 at 01:08:55AM +0900, Ryota Ozaki wrote:
>> Heh. Well so this is not a problem of routing. Just to be sure
>> please show me outputs of "tcpdump -e" of both ping6 and telnet?
>
> I'll attach the tcpdump output.  It's unfiltered and contains some
> irrelevant stuff, but it's not too bad.  I start with the "ping6
> netbsd.org" command and follow it with the "telnet netbsd.org www"
> command until the IPv6 connection times out.

Thanks. MAC addresses and IP addresses of packets of ping6 and telnet
are the same so the issue should come from L4 or above.

BTW I'm a bit surprised an ICMP6 echo reply returns from a different
MAC address from one that a request goes to.

>
>> And can you check where a SYN packet of telnet reaches? Does the packet
>> go out the Linux host?
>
> I guess you mean tcptraceroute.  Strangely, it goes almost all the way
> to the end (this is again on NetBSD-8.)  But, with telnet, it stays in
> SYN_SENT until timeout.

Oh sorry, I suppose to see packets of telnet by tcpdump on br0 and eth0
of Linux. I suspected that a SYN packet is broken and filtered out on the
interfaces for some reasons. And also we may see a SYNACK packet on
the interfaces if a SYN packet reaches the server.

>
> # tcptraceroute6 netbsd.org
> traceroute to netbsd.org (2001:470:a085:999::80) from 2620:105:c000:3:58a4:a8c:71ce:44f9, port 80, from port 61779, 30 hops max, 60 bytes packets
>  1  2620:105:c000:3::4 (2620:105:c000:3::4)  0.066 ms  0.729 ms  1.808 ms
>  2  2620:105:c000:1:1::1 (2620:105:c000:1:1::1)  0.530 ms  2.849 ms  1.008 ms
>  3  2620:105:c000:1::1 (2620:105:c000:1::1)  2.499 ms  1.896 ms  1.375 ms
>  4  * 2001:438:fffe::2e1 (2001:438:fffe::2e1)  1.967 ms  1.081 ms
>  5  ae14.cr2.ord2.us.zip.zayo.com (2001:438:ffff::407d:1895)  1.367 ms  0.966 ms  1.243 ms
>  6  * ae17.er2.ord7.us.zip.zayo.com (2001:438:ffff::407d:1f53)  2.804 ms  1.737 ms
>  7  10gigabitethernet1-8.core1.chi1.he.net (2001:470:0:341::1)  12.973 ms  12.152 ms  1.322 ms
>  8  * 10ge15-2.core1.den1.he.net (2001:470:0:1af::2)  25.500 ms  36.175 ms
>  9  100ge3-2.core1.sjc2.he.net (2001:470:0:3a2::1)  54.481 ms  50.840 ms  50.775 ms
> 10  * 10ge1-1.core1.fmt1.he.net (2001:470:0:2f::1)  59.203 ms  51.168 ms
> 11  10ge2-1.core2.fmt1.he.net (2001:470:0:1a7::2)  51.908 ms  * 56.450 ms
> 12  tserv1.fmt1.he.net (2001:470:0:308::2)  51.738 ms  52.845 ms  51.032 ms
> 13  riz-pt.tunnel.tserv1.fmt.ipv6.he.net (2001:470:1f00:ffff::3e5)  54.698 ms  51.813 ms  52.261 ms
> 14  * * *
> 15  * * *
> 16  * * *
> 17  * * *
> 18  * * *
> 19  * * *
> 20  * * *
> 21  * * *
> 22  * * *
> 23  * * *
> 24  * * *
> 25  * * *
> 26  * * *
> 27  * * *
> 28  * * *
> 29  * * *
> 30  * * *

Hm? I'm not sure why it doesn't finish while ping6 netbsd.org is success...

  ozaki-r