Development issues regarding the cerowrt test router project
 help / color / mirror / Atom feed
From: Michael Richardson <mcr@sandelman.ca>
To: Dave Taht <dave.taht@gmail.com>
Cc: Mikael Abrahamsson <swmike@swm.pp.se>,
	cerowrt-devel@lists.bufferbloat.net
Subject: Re: [Cerowrt-devel] ipv6 on comcast with 18.06.1
Date: Mon, 01 Oct 2018 13:13:31 -0400	[thread overview]
Message-ID: <32226.1538414011@localhost> (raw)
In-Reply-To: <CAA93jw67meaOWsL5BAk8uxYwn9DyFQCSK78N8Lk8mLc5mTOEYg@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 845 bytes --]


Dave Taht <dave.taht@gmail.com> wrote:
    > hmm... bad udp checksum???

With some capture mechanisms, tcpdump gets bogus values because the hardware
did the checksums.  I wouldn't imagine that we have hardware checksum offload
on openwrt devices, but could be.

Or it's a real issue.

    > :/tmp# 09:12:17.404257 IP6 (flowlabel 0xdfff4, hlim 1, next-header UDP
    > (17) payload length: 159) fe80::20d:b9ff:fe43:a06c.546 > ff02::1:2.547:
    > [bad udp cksum 0x58f4 -> 0xc4a1!]  On Mon, Oct 1, 2018 at 9:12 AM Dave
    > Taht <dave.taht@gmail.com> wrote:

Did you capture with -i device, or -i any?

--
]               Never tell me the odds!                 | ipv6 mesh networks [
]   Michael Richardson, Sandelman Software Works        | network architect  [
]     mcr@sandelman.ca  http://www.sandelman.ca/        |   ruby on rails    [


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 487 bytes --]

  parent reply	other threads:[~2018-10-01 17:13 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-01 15:30 Dave Taht
2018-10-01 15:45 ` Mikael Abrahamsson
2018-10-01 15:58   ` Dave Taht
2018-10-01 16:12     ` Dave Taht
2018-10-01 16:12       ` Dave Taht
2018-10-01 16:29         ` Anderson, Charles R
2018-10-01 16:44           ` Dave Taht
2018-10-01 17:13         ` Michael Richardson [this message]
2018-10-01 17:22           ` Dave Taht
2018-10-01 19:07       ` Mikael Abrahamsson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://lists.bufferbloat.net/postorius/lists/cerowrt-devel.lists.bufferbloat.net/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=32226.1538414011@localhost \
    --to=mcr@sandelman.ca \
    --cc=cerowrt-devel@lists.bufferbloat.net \
    --cc=dave.taht@gmail.com \
    --cc=swmike@swm.pp.se \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox