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Does Cisco ASA 5512-X support IPv6 /56 6rd delegated prefix from CenturyLink?

Sam Brynes

I have CenturyLink, which uses a 6rd IPv6 deployment where they hand out an IPv6 delegated prefix /56 block to me.


I'd like to break this /56 into multiple /64 blocks and use these for each of the ASA routed SVIs, and advertise these in neighbor advertisements so that IPv6 clients on each VLAN can pick up the prefix and add their EUI-64 to the back of the IPv6 address to get their global unicast address.


Does the Cisco ASA 5512-X support IPv6 6rd and the topology described above? I am considering a upgrade to support 6rd.

2 Replies 2

Thanks. This document talks about DHCPv6 prefix delegation, which I don't think is the same thing as 6rd prefix delegation.


This is a link to the RFC. It states:


"The 6rd delegated prefix for use at a customer site is created by
combining the 6rd prefix and all or part of the CE IPv4 address.
From these elements, the 6rd delegated prefix is automatically
created by the CE for the customer site when IPv4 service is
obtained. This 6rd delegated prefix is used in the same manner as a
prefix obtained via DHCPv6 prefix delegation [RFC3633]."


The 6rd delegated prefix is used in the same manner as... DHCPv6 prefix delegation (but is not the same thing).

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