nanog mailing list archives
Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker
From: William Herrin <bill () herrin us>
Date: Sun, 18 Nov 2012 23:49:39 -0500
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
Current thread:
- Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Constantine A. Murenin (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Doug Barton (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Sander Steffann (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Brandon Ross (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Bryan Fields (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Jon Lewis (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker John Levine (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker William Herrin (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Owen DeLong (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Dan Luedtke (Nov 20)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Jon Lewis (Nov 18)
- Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker Dylan N (Nov 19)