mysidia at gmail.com
Sun Sep 14 21:19:42 UTC 2014
On Sat, Sep 13, 2014 at 5:33 AM, Tarko Tikan <tarko at lanparty.ee> wrote:
> 2000::/64 has nothing to do with it.
> Any address between 2000:0000:0000:0000:0000:0000:0000:0000 and
> 23ff:ffff:ffff:ffff:ffff:ffff:ffff:ffff together with misconfigured prefix
> length (6 instead 64) becomes 2000::/6 prefix.
It should be rejected for the same reason that 192.168.10.0/16 is
invalid in a prefix list or access list.
Any decent router won't allow you to enter just anything in that range
into the export rules with a /6, except 2000:: itself, and will
even show you a failure response instead of silently ignoring the
invalid input, for the very purpose of helping you avoid such errors.
2001::1/6 would be an example of an invalid input -- there are
one or more non-zero bits listed outside the prefix, or where bits in
the mask are zero.
Only 2000:0000:0000:0000:0000:0000:0000:0000/6 properly conforms,
not just "any IP" in that range can have a /6 appended to the end.
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