[c-nsp] CE routes

[Ivan Pepelnjak]

CE-PE subnets are part of VRF and thus cannot be inserted into the core IGP,
only in MP-BGP. It's way easier (and more scalable) to redistribute them
than to list them in the per-VRF BGP configuration.

Ivan
 
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> -----Original Message-----
> From: harbor235 [mailto:harbor235 at gmail.com] 
> Sent: Tuesday, July 14, 2009 6:51 PM
> To: cisco-nsp at puck.nether.net
> Subject: [c-nsp] CE routes
> 
> I was just reading best practices for MPLS implementations 
> regarding CE to CE connectivity issues, specifically, CE to 
> CE pings. The document stated that redistributing connected 
> PE routes into BGP was the preferred method to ensure CE to 
> CE ping success as well as other connectivity issues. This 
> will inject the route for the PE to CE interface into BGP.I 
> am not sure I agree,  why not explicitly define which 
> networks to advertise in the IGP, an IGP in MPLS networks is 
> supposed to hold all infrastructure routes anyway. Are these 
> interfaces considered infrstructure or customer interfaces? 
> One reason may be to reduce the number of infrastructure 
> routes in the IGP because of the potential for many CE to PE 
> interfaces, let BGP handle the large number of routes?
> 
> I am curious which method is employed in the wild, also I am 
> not sure all connected routes should be advertised from the 
> PE, e.g. management/infrastructure interfaces etc ...
> 
> What are your thoughts and how is it being done?
> 
> mike
> 
>