[c-nsp] DHCPv6 on IOS-XR with multiple pools?

[Bryan Holloway]

Howdy all ...

Consider a Cisco 4900 with two L3-anchored VLANs in a GPON/FTTx-type 
scenario: one for business customers, and one for residential.

Both VLANs have a unique local /64 for customer ONTs, but I also want to 
do PD with /56s.

I learned quickly that the 4900 doesn't do DHCPv6 serving, but it will 
happily relay.

Upstream we have an ASR running 5.3.4.

On it I've been successful in creating "dhcp ipv6" server profiles, 
"prefix-pools", "address-pools" and subsequently anchoring them to the 
downstream interface facing the 4900, but I don't appear to be able to 
differentiate between pools for the two VLANs.

That is, I see assignments, but I'm not sure if the IOS-XR 
implementation supports having multiple prefix-pools and address-pools 
bound to a single downstream interface. It always appears to pick one or 
the other, no matter what I do with the config.

I see that there is a way to create "class"es within the "dhcp ipv6" 
config, but it doesn't seem to really do anything. That is, I can create 
a RESIDENTIAL class with its own address-pool and prefix-pool, and 
likewise a BUSINESS class with its own address-pool and prefix-pool, but 
the ASR doesn't seem to match the incoming request from the relaying 
4900 interface and choose the correct pool(s).

Anyone made this work before? I can send config examples if it helps. 
I've searched the docs but what I've found is a little sketchy.

N.B.: And yes -- I should probably be doing this with a proper DHCP 
server ... but I'm in a bit of crunch.

Thanks!
			- bryan