From: Ido Schimmel <idosch@idosch.org>
To: valdis.kletnieks@vt.edu
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: 4.14.(44->48) IPv6 RA issue?
Date: Mon, 18 Jun 2018 22:09:26 +0300 [thread overview]
Message-ID: <20180618190926.GA18065@splinter> (raw)
In-Reply-To: <35958.1529334166@turing-police.cc.vt.edu>
On Mon, Jun 18, 2018 at 11:02:46AM -0400, valdis.kletnieks@vt.edu wrote:
> So I'm trying to troubleshoot an issue on an OpenWRT/Lede based
> router, where IPv6 connectivity totally fails. I've bisected it down to:
>
> git log --oneline 187da94808a634477b5e5a69109ea0c566dfa64b..73d8a6ab7668173d70adbed45b61be5256c505e
> 73d8a6ab7668 (refs/bisect/bad) base-files: fix UCI config parsing and callback handling
> e52f3e9b1376 kernel: bump 4.14 to 4.14.48
> 7590c3c58f5e (HEAD) scripts: Replace obsolete POSIX tmpnam in slugimage.pl with File::Temp function
> 987900f2de76 hostapd: properly build hostapd-only SSL variants
>
> and am pretty sure that it's the kernel bump (works with a 4.14.44 kernel,
> breaks with 4.14.48) as the other 3 commits don't go anywhere near IPv6 handling.
...
> Note that eth1 is the uplink towards my ISP. I've pointed a 'tcpdump -n -i eth1 ip6'
> at it, and see plenty of RA packets come in, but neighbor discovery never completes.
> Looking at the Changelogs for .45->.50 don't show any smoking-gun patches.
>
> This ring any bells, before I delve deeper into it?
If this is a router and forwarding is enabled, then you need to set
'accept_ra' to '2' [1]. Is this what you have configured? Seems that
OpenWRT recently started to explicitly set 'accept_ra' to '0' [2].
1. https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt
2. https://github.com/openwrt/openwrt/commit/bb46520159c0119e829900e29681feea6f297fe0
prev parent reply other threads:[~2018-06-18 19:09 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-18 15:02 4.14.(44->48) IPv6 RA issue? valdis.kletnieks
2018-06-18 19:09 ` Ido Schimmel [this message]
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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180618190926.GA18065@splinter \
--to=idosch@idosch.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=valdis.kletnieks@vt.edu \
/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;
as well as URLs for NNTP newsgroup(s).