OK. I'm pretty sure I'm gonna get some flak for this but I'll share this question and it's background anyway. Please be gentle. In the past, with IPv4, we have used reserved or "non-routable" space Internally in production for segments that won't be seen anywhere else. Examples? A sync VLAN for some FWs to share state. An IBGP link between routers that will never be seen or advertised. In those cases, we have often used 192.0.2.0/24. It's reserved and never used and even if it did get used one day we aren't "routing" it internally. It's just on segments where we need some L3 that will never be seen. On to IPv6 I was considering taking the same approach. Maybe using 0100::/8 or 1000::/4 or A000::/3 as a space for this. Other than the usual "Hey, you shouldn't do that" can anyone give me some IPv6 specific reasons that I may not be forecasting that would make it worse doing this than in an IPv4 scenario. I know, not apples to apples but for this question they are close enough. Unless there is something IPv6 specific that is influencing this.... -- -Hammer- "I was a normal American nerd" -Jack Herer