[c-nsp] IPV6

[TJ]

Just minor added comments ... 

> -----Original Message-----
> From: cisco-nsp-bounces at puck.nether.net [mailto:cisco-nsp-
> bounces at puck.nether.net] On Behalf Of Phil Mayers
> Sent: Friday, December 11, 2009 11:41
> 
> Michael Robson wrote:
> > It's been a while since I worked with IPV6 and I am now once again
> > plunging myself into this feckless world and was wondering if a
> > couple of holes had now been plugged. What is the accepted way in
> > IPV6 land to dish out IPV6 DNS server addresses (am I correct in
> > saying that if you make use of NDP, you would still have to manually
> > configure DNS servers)? The other hole, as was, is the lack of IPV6
> 
> There are 4 methods:
> 
>   * Don't use IPv6 DNS - use IPv4 DNS servers (via DHCPv4 or other). I
> believe this is pretty common

This is how WinXP does it, both IPv4 and IPv6 (A and AAAA) queries being
sent over IPv4.  I like to call it "cheating" :).


>   * Static config of IPv6 DNS servers, possibly using an anycast address
> (I seem to recall there are products which try a well-known DNSv6
> address, but I can't remember what products, and what address)

If you are thinking of the fec0:0:0:ffff::1 (and ::2 and ::3) style
addresses those died along with Site-Local Addressing. (But you will still
see those entries in every IPv6-enabled Win* platform ... )

(Automagic DNS -->
http://tools.ietf.org/html/draft-ietf-ipv6-dns-discovery-07 
 SLAs deprecated --> http://tools.ietf.org/html/rfc3879
)


>   * Advertisment in RA packets - RFC 5006. I think support for this on
> IOS is pretty thin - I'm fairly sure 6500s don't support it and don't
> have it roadmapped (sigh)

Also waiting for client-side support.  (sigh+=1)


>   * DHCPv6
> 
> > help address functionality on Cisco routers (well 6500s at least): if
> > I were to go down the route of using DHCP for IPV6, how could I use a
> > central server without this helper functionality?
> 
> 6500s running SXI have gained the DHCPv6 relay support. Sadly, it
> doesn't interoperate with 6vPE (which we use) so I've only tested it
> lightly, but it more or less worked.
> 
> Of course, many clients don't support DHCPv6 (e.g. WinXP) so you may
> still need a solution for those.


... baby steps ... tiny, agonizingly slow, sometimes wobbly baby steps.
/TJ