Routing Metrics - Redistributing from MP-BGP VPNv4 into EIGRP

Good evening all.

Doing labs on PE-CE (namely EIGRP).

I have a PE router (PE-1) which has an EIGRP adjacency (within a VRF)
with a downstream CE router.

PE-1 is receiving MP-BGP VPNv4 routes from another PE (PE-2) sitting
across an MPLS network. PE-2 is advertising routes from two difference
VRFs, both of which are running different routing protocols (let's say
the customer has one floor in a building running EIGRP as the PE-CE and
another floor running OSPF as the PE-CE). Not a real world scenario,
just a twisted and messed up way of doing things, i.e. preparation for
the CCIE lab. ;)

PE-1 needs to accept both of these routes into the EIGRP topology table
and advertise them down to the CE router. Obviously the routes which
were originally EIGRP routes will appear as EIGRP internal routes and
the OSPF routes will appear as EIGRP external routes in the CE's routing
table.

After setting the correct RT's (route-targets), the routes do appear to
be learned via MP-BGP VPNv4, which is good:

sh bgp vpnv4 uni vrf CA | b Net
      Network Next Hop Metric LocPrf Weight Path
Route Distinguisher: 1:10 (default for vrf CA)
  *>i 5.0.0.0 4.4.4.4 13556702 100 0 ?
  *>i 6.0.0.0 4.4.4.4 11 100 0 ?

You can tell which is the internal EIGRP and which is the external EIGRP
based on the metric values.

The 5.0.0.0/8 route will have no problems with metrics when
redistributed back into EIGRP because of the extended community values
which get propagated along with the VPNv4 route, i.e. we don't have to
specify metrics:

sh bgp vpnv4 uni vrf CA 5.0.0.0/8
BGP routing table entry for 1:10:5.0.0.0/8, version 8
Paths: (1 available, best #1, table CA)
   Not advertised to any peer
   Refresh Epoch 2
   Local, imported path from 1:50:5.0.0.0/8 (global)
     4.4.4.4 (metric 21) from 4.4.4.4 (4.4.4.4)
       Origin incomplete, metric 13556702, localpref 100, valid,
internal, best
       Extended Community: RT:1:105
         Cost:pre-bestpath:128:13556702 (default-2133926945) 0x8800:32768:0
         0x8801:100:512032 0x8802:65281:1657856 0x8803:65281:1500
         0x8806:0:84215045
       mpls labels in/out nolabel/403
       rx pathid: 0, tx pathid: 0x0

The 6.0.0.0/8 route however will need to have a EIGRP metric set for it,
due to the fact that its VPNv4 extended community values (OSPF) mean
nothing to EIGRP:

sh bgp vpnv4 uni vrf CA 6.0.0.0/8
BGP routing table entry for 1:10:6.0.0.0/8, version 14
Paths: (1 available, best #1, table CA)
   Not advertised to any peer
   Refresh Epoch 3
   Local, imported path from 1:60:6.0.0.0/8 (global)
     4.4.4.4 (metric 21) from 4.4.4.4 (4.4.4.4)
       Origin incomplete, metric 11, localpref 100, valid, internal, best
       Extended Community: RT:1:600 RT:1:615
         OSPF DOMAIN ID:0x0005:0x000000020200 OSPF RT:0.0.0.0:2:0
         OSPF ROUTER ID:10.1.46.4:0
       mpls labels in/out nolabel/406
       rx pathid: 0, tx pathid: 0x0

My goal is to continue to use the EIGRP metrics for the EIGRP internal
routes, and set new EIGRP metrics for the external routes. I only seem
to be able to use one redistribute command under the EIGRP process
running within the VRF on PE-1. So I need to use a route-map along with
the redistribution back into EIGRP.

My question is what on earth do I match on for the EIGRP external routes
(ACL is too easy, I want to use some of the other match options in the
route-map)?

router eigrp AS100
  address-family ipv4 unicast vrf CA autonomous-system 100
   topology base
    redistribute bgp 65001 route-map REDIS-EIGRP

route-map REDIS-EIGRP permit 10
  match ?????
  set metric 1500 1 1 1 1500

route-map REDIS-EIGRP permit 20

The sensible options appear to be "match source-protocol" or "match
route-type", but I can't get either to work properly.

If I do "match route-type external" it drops the external routes
completely, but keeps the EIGRP ones.
If I do "match source-protocol ospf 2" it appears to match both the
internal and external ones and sets the metrics on both types of routes???

The other option is for me to TAG the OSPF routes on PE-2 as they get
redistributed into MP-BGP VPNv4 and then match on that when they get
redistributed back on PE-1. But I want to understand the route-map
options better.

Thanks.

Billy

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Received on Sun Aug 31 2014 - 00:27:34 ART