From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roy Marples <roy@marples.name>
Subject: [PATCH] ipv6: do not add link-local address if one already exists
Date: Sun, 10 Aug 2014 19:56:05 +0000
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Cc: "David S. Miller\" <davem@davemloft.net>, Alexey Kuznetsov
	<kuznet@ms2.inr.ac.ru>, Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	Patrick McHardy" <kaber@trash.net>
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Hi

Currently the kernel will always add an IPv6 link-local address
based on the hardware address when the interface is brought up.
This is probably based on the assumption that userland would
never add one before the interface is brought up.

However, one at least one userland application (dhcpcd) does this so
it can implement RFC7217 which can be used for link-local addresses
as well.

Attached is a patch which checks to see if a link-local address exists
before indiscriminately adding one.

Thanks

Roy
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