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Re: [v6ops] DAD again [was: draft-ietf-v6ops-host-addr-availability discussion]

Gert Doering <gert@space.net> Sat, 14 November 2015 18:12 UTC

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Date: Sat, 14 Nov 2015 19:12:40 +0100
From: Gert Doering <gert@space.net>
To: "Hemant Singh (shemant)" <shemant@cisco.com>
Message-ID: <20151114181240.GI89490@Space.Net>
References: <D76E6E81-419B-459D-AF5F-A6B8781CF445@delong.com> <a562066cf4d14f80aa94de314c27d632@XCH-RTP-005.cisco.com> <F5469EDB-E8E3-459A-ACF0-C9B2F11A8968@delong.com> <1c64119717ac4cc5a1e88dc8175af92f@XCH-RTP-005.cisco.com> <38D33D99-5075-4A52-9B57-9FEC9B088EF0@delong.com> <dcc3058655eb45319b5f2431db9667b0@XCH-RTP-005.cisco.com> <8A25D382-C4C6-4FBA-B5FF-D10BD4F398A9@delong.com> <158e13b7080a494cb3503476dc378a1e@XCH-RTP-005.cisco.com> <EFB44958-1C5D-4F08-9859-275489392B3D@delong.com> <a4050b82cc954ac8b25f50dc985451c9@XCH-RTP-005.cisco.com>
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Subject: Re: [v6ops] DAD again [was: draft-ietf-v6ops-host-addr-availability discussion]
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Hi,

On Sat, Nov 14, 2015 at 12:36:03AM +0000, Hemant Singh (shemant) wrote:
> routeri#clear ipv6 neigh                                  
> routeri#
> router#ping 2001:db8:3800:800:250:56FF:FEB2:F11D source lo0
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 2001:db8:3800:800:250:56FF:FEB2:F11D, timeout is 2 seconds:
> Packet sent with a source address of 2004::1
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms
> router#

This, actually, is a totally meaningless example.

I can send packets round the world with any source address I choose, and
it has no significance for on-link NS or DAD with the *on-link* address
of intermediate network segments.

If you look more closely at your box, you'll see that it will not use the
2004::1 source address for ND on the next-hop lan interface.

Gert Doering
        -- NetMaster
-- 
have you enabled IPv6 on something today...?

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