v6 subnet size for DSL & leased line customers

Marshall Eubanks tme at multicasttech.com
Fri Dec 28 03:17:18 UTC 2007

On Dec 27, 2007, at 9:50 PM, Robert E. Seastrom wrote:

> Leo Bicknell <bicknell at ufp.org> writes:
>> In a message written on Thu, Dec 27, 2007 at 10:57:59PM +0100,  
>> Iljitsch van Beijnum wrote:
>>> It is wih IPv6: you just connect the ethernet cable and the RAs take
>>> care of the rest. _You_ _really_ _don't_ _need_ _DHCP_ _for_ _IPv6_.
>>> If you need extreme control then manual configuration will give you
>>> that, which may be appropriate in some cases, such as servers.
>> Really.  I didn't know RA's could:
>> - Configure NTP servers for me.
>> - Tell me where to netboot from.
>> - Enter dynamic DNS entries in the DNS tree for me.
>> - Tell me my domain name.
>> - Tell me the VLAN to use for IP Telephony.
>> Those are things I use on a regular basis I'd really rather not
>> manually configure.
> I'm running (native) IPv6 at home, and in the colo too.  Most of my
> ssh sessions to personally owned machines go over v6.
> My laptops (with a single exception) are Macs.  You may not be aware
> that the Mac is fairly smart about which interface it uses for
> connections - it will prefer the gigabit ethernet to the wireless when
> it sees link...  it prefers wireless to dialup too.  Basically,
> whenever you establish a new outgoing session it will use the "lowest
> cost" interface to do the deed.
> For IPv4, I have the same address manually assigned on the DHCP server
> to both the gigabit ethernet's MAC address and the wireless
> interface's MAC address.  This means that when I plug into the gige,
> as I do for filesharing or backing some files up, the Mac uses the
> gigabit ethernet.  When I unplug and carry the Mac to the conference
> room, *all existing upper layer sessions are preserved* - TCP and
> friends are blissfully unaware that a change has taken place; one
> gratuitous arp so the router knows where to send the packets and we're
> on our way again with nary a hiccup.  I don't have an ssh session
> croak just because I connected or disconnected a cable.
> I'd really, really, really like to have DHCP6 on the Mac.  Autoconfig
> is not sufficient for this task unless there is some kind of trick you
> can do to make the eui-64 come out the same for both interfaces (don't
> think so).
> Anyone from Apple reading this list?  :-)

Don't know, but I bet they read  the MacnetworkProg list - they are  
present on all the Apple hosted lists
I am on. See

http://lists.apple.com/mailman/listinfo/macnetworkprog  from



>                                         ---Rob

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