Been discussing this with people and reading up, would like people's thoughts on whether or not its worth running IPv6 in a VRF or just let it loose in the global routing table.
Even though presently we use a VRF topology for various reasons, for IPv6 I am strongly on the side of running it natively
– resource consumption (thinking of full internet routing tables in IPv6 in a VRF, yech)
– no more multiple routing processes per router
– lots of our present HW that is not going to go EOL in the next year or two struggles with IPv6 in a VRF (3750, 3560)
For purposes of 'mimicking' VRF separation for areas that require it going to bite the bullet and put firewalls where I need, the only alternative (short of mirroring the present VRF topology) is to go to a nightmare of tunnels and PBRS
I guess the penny dropped when reading about IPv6 on MPLS 6PE.
Thoughts appreciated (especially the ones telling me I'm wrong! its how I learn lol)
Best Answer
IPv4 and IPv6 operate as 'ships in the night' as far as routing is concerned, so I see not benefit to separate VRFs with ipv4 in one and ipv6 in another. Also any dual stack hosts would need separate interfaces or separate tagged VLANs to operate dual stack. Now if you are concerned about RAM in the router VRF will not help that, for that concern route summarization or default routing would help there, and that applies to both IPv6 and ipv4