[c-nsp] Internet in VRF

[Mike]

On 05/01/2015 12:00 PM, Mark Tinka wrote:
>
> On 30/Apr/15 18:41, Mike wrote:
>> Hi,
>>
>>      I'd like to ask for the collective opinion on routing in service
>> provider network serving broadband subscribers:
>>
>>      I have an ASR1k and will be terminating PPPoE broadband
>> subscribers here. I'll also be terminating my primay internet feed
>> (BGP) here, and I the future I will have 3 providers and will be
>> multihomed. I also will have some MPLS vpns for certain customers.
>>
>>      I think I want to have my default routing table carry mostly
>> loopbacks and direct interface connected routes, while I want to stuff
>> everything else into VRF's. Those other VRF's are likely to be
>> Internet (full tables), Subscribers (all the /32's for PPPoE
>> subscribers), and the odd vrf for any mpls vpn customers.  The
>> challenge is that - I think - I would want to only leak a default
>> route into any other non-Internet VRF that requires shared service
>> access to it, which should keep the table sizes down. My question is,
>> does this sound reasonable? Is there any reason I wouldn't want to set
>> things up this way?
> I like simple.
>
> Internet routes in a VRF is not simple - too dependent on hardware and
> software capabilities, without having to worry about what the vendors do
> with the hardware or the software in future revisions.
>
> I know a few ISP's that went this router back in 2003, when MPLS was
> all-the-rage; they're finding that tearing down this wall of complexity
> is the way forward, but alas, mighty painful.
>

What exactly are the downsides? I don't have 100's of routers and 
transits and peerings and such, but if I'm going to be painting myself 
into a corner I'd like to know about it before it do it.

Thank you.