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Re: evil ipv6 bit?


From: Saku Ytti <saku () ytti fi>
Date: Fri, 26 Jan 2018 15:55:58 +0000

On 26 January 2018 at 03:50, Baldur Norddahl <baldur.norddahl () gmail com> wrote:


I just now discovered this:

google.com: 2a00:1450:400e:807::200e

That address works fine. But then I changed that one bit in the address:
2a00:1450:400e:8807::200e and voila, the router drops the packet.

Now I am stumbled. What could the 49th bit in the destination IPv6 address
field in a packet mean to the router, that would make it drop the packet?

Are you sure it is dropped? Can you see some drop counter increase?
Have you observed nothing coming out from any port?

My guess is bad memory, and that bit is statically set or statically
unset and cannot be changed. Might cause CRC error, IP checksum error
or just mangled packet coming out of the router


-- 
  ++ytti


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