From: Andrew Morton <akpm@linux-foundation.org>
To: netdev@vger.kernel.org
Cc: bugzilla-daemon@bugzilla.kernel.org,
bugme-daemon@bugzilla.kernel.org, ghen@telenet.be
Subject: Re: [Bugme-new] [Bug 28512] New: IPv6 SLAAC address preferred over static one as source address
Date: Mon, 7 Feb 2011 15:20:48 -0800 [thread overview]
Message-ID: <20110207152048.22c51184.akpm@linux-foundation.org> (raw)
In-Reply-To: <bug-28512-10286@https.bugzilla.kernel.org/>
(switched to email. Please respond via emailed reply-to-all, not via the
bugzilla web interface).
On Mon, 7 Feb 2011 16:15:16 GMT
bugzilla-daemon@bugzilla.kernel.org wrote:
> https://bugzilla.kernel.org/show_bug.cgi?id=28512
>
> Summary: IPv6 SLAAC address preferred over static one as source
> address
> Product: Networking
> Version: 2.5
> Kernel Version: 2.6.36
> Platform: All
> OS/Version: Linux
> Tree: Mainline
> Status: NEW
> Severity: normal
> Priority: P1
> Component: IPV6
> AssignedTo: yoshfuji@linux-ipv6.org
> ReportedBy: ghen@telenet.be
> Regression: No
>
>
> Linux IPv6 source address selection rules are described here:
> http://www.davidc.net/networking/ipv6-source-address-selection-linux
>
> In case of a tie, "Linux chooses to use the latest address added".
>
> A very common tie is where a host has a SLAAC (Stateless address
> auto-configuration) address as well as one or more statically assigned ones in
> the same /64. The SLAAC address will almost always be the most recently
> "added" one, as it is renewed with every Router Advertisement on the network,
> and there will be a tie for all other rules.
>
> As a consequence, the kernel chooses this address by default for outgoing
> connections. This is usually not the preferred scenario; the static address
> will more likely have proper reverse DNS, be configured in ACL's, etc.
>
> This has been discussed on the ipv6-ops mailing list
> (ipv6-ops@lists.cluenet.de), and a better suggestion for a tie-breaker came
> out: the preferred lifetime of the address.
>
> SLAAC addresses will have a limited preferred lifetime (as defined by the
> router), static addresses will usually have an unlimited preferred lifetime
> (0). So it makes a lot of sense to take this preferred lifetime into account
> for source address selection (how is it otherwise "preferred"?).
>
> This could be added as rule #9 before using the most recently added as a final
> tie breaker?
>
> Geert
next parent reply other threads:[~2011-02-07 23:21 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <bug-28512-10286@https.bugzilla.kernel.org/>
2011-02-07 23:20 ` Andrew Morton [this message]
2011-03-30 0:20 ` [Bugme-new] [Bug 28512] New: IPv6 SLAAC address preferred over static one as source address David Miller
2011-03-30 7:31 ` Geert Hendrickx
2011-03-30 8:59 ` David Miller
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=20110207152048.22c51184.akpm@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=bugme-daemon@bugzilla.kernel.org \
--cc=bugzilla-daemon@bugzilla.kernel.org \
--cc=ghen@telenet.be \
--cc=netdev@vger.kernel.org \
/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).