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Re: Long and unabbreviatable IPv6 addresses with random overloaded bits, vs. tunnelbroker
From: Jon Lewis <jlewis () lewis org>
Date: Sun, 18 Nov 2012 19:53:07 -0500 (EST)
On Sun, 18 Nov 2012, Bryan Fields wrote:
On 11/18/12 5:53 PM, Constantine A. Murenin wrote:edis.at gives you an IPv4 address of, for example, 158.255.21x.xxx, and the IPv6 /112 that you get is 2a03:f80:ed15:158:255:21x:xxx:0/112 (really a /48), with 2a03:0f80:ed15::1 as the gateway.
By "KVM", I assume he's talking about cloud or VPS, i.e. a KVM based virtual machine. With cloud in particular, I've been trying to decide how to dole out IPv6 space. Because we're doing bridged networking for the VMs, we've been giving out IPv4 /32s to each VM and all VMs are in the same VLAN.
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.
---------------------------------------------------------------------- Jon Lewis, MCP :) | I route Senior Network Engineer | therefore you are Atlantic Net | _________ http://www.lewis.org/~jlewis/pgp for PGP public key_________
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)