Re: comcast ipv6 PTR

[Bjørn Mork <bjorn () mork no>]

Lee Howard <Lee () asgard org> writes:

> The 6renum WG at IETF just closed, with a list of work items remaining for
> other WGs to complete.  I recommend RFC6879 in particular, with RFC6866
> describing some parts of the problems and RFC7010 being the outstanding
> work.
>
> The IETF has generally been taken as an assumption that the home network
> is 
>
> unmanaged (see the Homenet charter and architecture document, for
> instance).
> The administrator of a managed network can follow RFC6879 and renumber
> pretty seamlessly.

Yes, given
 - careful planning
 - smart macro usage
 - some scripting

Feel free to show me a typical business site with more than 2 of those
in place...

FWIW, I did a little exercise on my home network, running just a few
basic services which I assume most businesses will run as well. This
resulted in a number of text configuration file formats requiring
requiring knowlegde of the prefix list (i.e. not suitable for DNS
names):
 - spamassasin (trusted_networks)
 - BIND (recursion allowed acl)
 - sendmail (relaying access)
 - ntp (peer access)
 - cups (printer access)
 - squid (http proxy access)

All of these use different configuration syntax and generally do not
support macro expansion of the prefix.  So you'd have to script any
updates.

I'm in particular fond of the sendmail and ntp syntaxes, which can best
be described as "weird".

sendmail:
 IPv6:2001:0db8:0f00     RELAY

ntp:
 restrict 2001:db8:f00:: mask ffff:ffff:ffff:: nomodify

When you can't even standardize on a prefix syntax, how the heck are you
going to make renumbering seamless??

> In the unmanaged home, since everything is automatic, renumbering
> should be seamless.

Most homes will have at least one manually configured IP device. Typical
candidates are 
 - printers
 - media (video and/or audio) playback devices
 - additional wlan access points

We can close our eyes and ignore them, but they are still there.  Yes,
yes, the firmware programmers are going to get much much smarter when
they add IPv6 to these devices.  I'm sure.

I'm still in favour of reducing the renumbering burden as much as
possible, even for home networks.


Bjørn