With DHCPv6, do manual address bindings not apply? I see manual bindings for prefix delegation but none for addresses.
In dhcpv4, there was the ability to specify a client-id (or hardware-address) and then use the command 'host a.b.c.d' to assign a specific address to a specific host.
In studying dhcpv6, I do not see a similar capability.
Wow, all those Cisco folks and CCIEs out there and nobody knows! I have either stumped or bored the world's experts.
Does anyone know the answer to my question?
Hope this helps.
If I understand your question, you are asking if you can do a one-to-one mapping between a client and an IPv6 address. Are you looking for this mapping to be a global, link local or unique local? What is the driver behind this requirement? If you have the DHCPv6 configured to hand out a /64 prefix then using the manipulation on the MAC address, you will know (predictably) what the address will be:
Here is what Cisco has to say about their implementation of DHCPv6 (from the first link):
The Cisco IOS Software DHCPv6 function runs in routers. It is based on RFC3315 DHCPv6 specification. Prefix Delegation [PD] and DNS [DNS] DHCPv6 options are supported and allow distribution of a prefix, as well as a list of DNS servers and domain names.
The Cisco IOS Software DHCPv6 client and server are specifically intended as a PD solution and do not implement the entire DHCPv6 protocol. Cisco IOS Software DHCPv6 currently implements PD, the rapid-commit mechanism, stateless DHCPv6 ("DHCPv6-lite"), and the following:
•Client Identifier option
•Server Identifier option
•Option Request option
•Status Code Option
•Rapid Commit option
•Identity Association for Prefix Delegation option (IA_PD option)
•IA_PD Prefix option
•Domain Name Server option
•Domain Search List option
Thank you , that is helpful. The server is handing out IA_NA and chooses the 'host' bits (those beyond the address prefix specified in the dhcpv6 pool.)
I was looking to see if I can also control the lower 64 bits being handed out.
I am not aware of a DHCPv6 server that does this. I believe that the expectation and design for IPv6 is that the host is responsible for this (per RFC 4862).
This document specifies the steps a host takes in deciding how to autoconfigure its interfaces in IP version 6. The autoconfiguration process includes generating a link-local address, generating global addresses via stateless address autoconfiguration, and the Duplicate Address Detection procedure to verify the uniqueness of the addresses on a link.
I hope that helps. To be clear, I am speaking of link-local addresses. Global addresses are a different matter when mapped to a DNS name. I would expect that any FQDN name would resolve to a static IPv6 address (or by some DDNS means).