On Sun, Nov 18, 2012 at 7:53 PM, Jon Lewis <jlewis@lewis.org> wrote:
It seems insane to try to setup a proper IPv6 subnet and unique gateway for each VM, so I've been thinking something similar to what the host being complained about here has done is the only way to go. Not down to the detail of making the IPv6 ip based on the IPv4 IP, but giving out "very small" v6 blocks, (i.e. maybe /120 or /124), out of a /48 with the prefix::1/48 IP as everyone's gateway. Sure, IPv6 is big enough that we could give out /64s from that /48 and not run out of numbers, but I'm concerned about what happens when an abusive customer turns up 2^64 addresses and overloads the neighbor discovery cache on our gear. What's anyone really going to do with more than a few IP addresses on a VPS anyway? Just as we do with additional v4 IPs, if someone really has a need for additional v6 subnets, those could be provided, likely for a fee.
Hi Jon, Why not assign a single IPv6 address to each VM and then for those folks who need more, *route* a /64 to the original address? With Linux, I think you can then attach the whole /64 to a loopback alias (lo:1) and the host will understand that it has the entire /64 without creating neighbor table entries or any other chancy things. Regards, Bill Herrin -- William D. Herrin ................ herrin@dirtside.com bill@herrin.us 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> Falls Church, VA 22042-3004