[101269] in North American Network Operators' Group
Re: v6 subnet size for DSL & leased line customers
daemon@ATHENA.MIT.EDU (Stephen Sprunk)
Wed Dec 26 00:17:00 2007
From: "Stephen Sprunk" <stephen@sprunk.org>
To: <sthaug@nethelp.no>
Cc: "North American Noise and Off-topic Gripes" <nanog@merit.edu>
Date: Tue, 25 Dec 2007 20:05:12 -0600
Errors-To: owner-nanog@merit.edu
Thus spake <sthaug@nethelp.no>
>> In places where you need tighter control over the usage of various
>> gateways on a common L2 segment, VRRP probably makes more
>> sense. However, as things currently stand, that means static routing
>> configuration on the host since for reasons passing understanding,
>> DHCP6 specifically won't do gateway assignment.
>
> For those of us with lots of IPv4 customers dependent on DHCP, it
> would be good to know more detail about this point. What is the
> problem, and are there plans to do anything about it in DHCPv6?
For most hosts, there is no need for anything like VRRP or getting a default
gateway via DHCP in v6 because all hosts are required to implement RA/RS.
The vast majority of hosts either have one default gateway or two-plus
equivalent ones, so that works fine. For hosts with multiple gateways that
are unequal, VRRP+DHCP doesn't solve the problem any better than RA/RS; you
have to fiddle with the hosts' routing tables to get things set up right.
S
Stephen Sprunk "God does not play dice." --Albert Einstein
CCIE #3723 "God is an inveterate gambler, and He throws the
K5SSS dice at every possible opportunity." --Stephen Hawking
