anycast address as deault router

[Michael K. Smith - Adhost]

> -----Original Message-----
> From: ipv6-ops-bounces+mksmith=adhost.com at lists.cluenet.de
> [mailto:ipv6-ops-bounces+mksmith=adhost.com at lists.cluenet.de] On
Behalf
> Of Nick Hilliard
> Sent: Wednesday, December 30, 2009 1:30 PM
> To: The Dark One
> Cc: ipv6-ops at lists.cluenet.de
> Subject: Re: anycast address as deault router
> 
> On 30/12/2009 21:25, The Dark One wrote:
> > supposing that on a LAN there are 2 routers (default-gateway) and
one
> > host and that the routers don't support any
> FirstHopRedundancyProtocol,
> > does it make sense to configure a anycast address on both routers
and
> > configure that as the default-gateway of the host?
> > If it does makes sense, is it also possible to have the routers
> > advertise that anycast address in their RA?
> 
> Sounds like this would fall foul of duplicate address detection.  I
> suspect
> both your routers and your leaf nodes would probably get very excited
> about
> this, and not necessarily in a good way either.
> 
> By all means try it out, but when it refuses to work, take a look at
> RFC2462 (section 5.4).
> 
> Nick

I had to do exactly this on my GSR's because they don't support RA
prioritization or HSRP v3 and most likely never will.  The anycasted
default gateway from two routers does work, although the failover
between routers is +/- 20 seconds.  If anyone would like a copy of the
configuration snippets just let me know.

Regards,

Mike