From: Stephen Hemminger <stephen@networkplumber.org>
To: David Ahern <dsahern@gmail.com>
Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>
Subject: Re: why are IPv6 addresses removed on link down
Date: Mon, 12 Jan 2015 23:10:21 -0800 [thread overview]
Message-ID: <20150112231021.316648e3@urahara> (raw)
In-Reply-To: <54B4A7E4.7030301@gmail.com>
On Mon, 12 Jan 2015 22:06:44 -0700
David Ahern <dsahern@gmail.com> wrote:
> We noticed that IPv6 addresses are removed on a link down. e.g.,
> ip link set dev eth1
>
>
> Looking at the code it appears to be this code path in addrconf.c:
>
> case NETDEV_DOWN:
> case NETDEV_UNREGISTER:
> /*
> * Remove all addresses from this interface.
> */
> addrconf_ifdown(dev, event != NETDEV_DOWN);
> break;
>
> IPv4 addresses are NOT removed on a link down. Is there a particular
> reason IPv6 addresses are?
>
> Thanks,
> David
See RFC's which describes how IPv6 does Duplicate Address Detection.
Address is not valid when link is down, since DAD is not possible.
next prev parent reply other threads:[~2015-01-13 7:10 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-13 5:06 why are IPv6 addresses removed on link down David Ahern
2015-01-13 7:10 ` Stephen Hemminger [this message]
2015-01-13 10:35 ` Hannes Frederic Sowa
2015-01-13 11:58 ` YOSHIFUJI Hideaki
2015-01-13 12:15 ` YOSHIFUJI Hideaki
2015-01-13 12:36 ` Hannes Frederic Sowa
2015-01-13 14:53 ` David Ahern
2015-01-13 15:00 ` Hannes Frederic Sowa
2015-01-13 17:05 ` Nicolas Dichtel
2015-01-13 15:00 ` Sowmini Varadhan
2015-01-13 15:09 ` Hannes Frederic Sowa
2015-01-13 15:13 ` Sowmini Varadhan
2015-01-13 17:25 ` David Miller
2015-01-13 17:34 ` Hannes Frederic Sowa
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