[j-nsp] Copy of inet.0

[John Payne]

On Oct 29, 2004, at 6:06 PM, Pedro Roque Marques wrote:

> Sorry, you will need to switch the instance type to
> virtual-router. Which is the same thing, expect that it can take
> interface statements...

OK... I seem to recall other differences with virtual-router, but I can 
try it again.

>> Will instance-import pull out individual routes from a multipath
>> setup?  ie if I have multiple active multipath routes to a
>> destination, can I use instance-import to grab one of them?  (Based
>> on community perhaps?)
>
> Depends on what you are refering to...
>
> There is prefix (route), path (route entry) and next-hop...
>
> i.e.	if you do a show route you will see something like
>
> 	prefix1
> 	    path 1
> 	         <ACTIVE>
> 		 nexthop a, b
> 	    path 2
> 	         Inactive due to: something.
> 	         nexthop c, d
>
> BGP will install multiple paths to the same prefix... IGPs will only
> install one path.
>
> instance-import will only pick the active path (path 1 above). This is
> how the mecanism is defined... and it serves to avoid the potential
> case where you would just be duplicating all received routing updates
> between tables.
>
> If you want/need path 2, maybe w/ different attributes, then you have
> to explicitly use rib-groups.


I have a set of devices advertising the same prefix.  Right now, I'm 
manually grouping them using rib-groups and then multipath from there, 
but I'd love to be able to move the groups around based on communities.

> You can pick between the multiple next-hops which one is used for
> forwarding via the install-next hop policy action on routing-options
> forwarding export policy.

Yeah, that's not the right place to make the decision in this case :)

> I hope i've not added to the confusion...

Nope.