Re: failure detection

[Paul Jakma <paul@clubi.ie>]

On Tue, 30 Aug 2005, marcelo bagnulo braun wrote:

> In this case, i guess you are considering that the host will choose 
> the source address containing prefix Pref1 when sending packets 
> with next hop router Soho1, right? would this be the case of 
> available implementations?

It is definitely the case for Linux and Solaris for IPv4. The source 
(if unspecified) is chosen according to which subnet the gateway is 
on. I'm hopeful its the same for IPv6.

> How would you deal with the following situation:
>
>     host
>      |
>  ----------
>      |
>    router3
>      |
> -----------
>   |     |
> SOHO1  SOHO2
>   |     |
> ISP1   ISP2
>
> In this case, router3 is internal to the SOHO site and it is announcing both 
> prefixes.

Router3 would have to forward according to source-address.

The question here though is: Who is doing the shimming? If the host, 
then the host needs to be informed somehow of local failures. Eg, 
router3's RAs to the host subnet would need to somehow be influenced 
by SOHO1 and SOHO2. (Some discussions on possibilities for this in 
other mails).

regards,
--
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