MPLS and EIGRP (from INE.com blog)

http://blog.ine.com/2010/07/19/mpls-and-eigrp-going-the-distance-admin-distance/comment-page-1/#comment-122111

and my comment:

This was really good, i had only done this type of lab before with OSPF and sham links, it took me some digging but pretty sure this is the answer:

BGP Cost Community Support for EIGRP MPLS VPN PE-CE with Backdoor Links The “pre-bestpath” point of insertion (POI) is applied automatically to EIGRP routes that are redistributed into BGP. The “pre-best path” POI carries the EIGRP route type and metric. This POI influences the best path calculation process by influencing BGP to consider this POI before any other comparison step. No configuration is required. This feature is enabled automatically for EIGRP VPN sites when Cisco IOS Release 12.0(27)S is installed to a PE, CE, or back door router.

http://www.cisco.com/en/US/docs/ios/iproute_bgp/configuration/guide/irg_cost_comm_ps6441_TSD_Products_Configuration_Guide_Chapter.html#wp1054113

I was also able to turn this ‘on/off’ with bgp bestpath cost-community ignore

And also by making the metric extremly worse on R4 f0/1 ; R2 will choose the path through R1 to get to 5.5.5.0

R2#sh ip route vrf v 5.5.5.0
Routing entry for 5.5.5.0/24
Known via “bgp 234″, distance 200, metric 409600, type internal
Redistributing via eigrp 1
Advertised by eigrp 1 metric 1 10000 1 1 1
bgp 234 (self originated)
Last update from 4.4.4.4 00:16:30 ago
Routing Descriptor Blocks:
* 4.4.4.4 (Default-IP-Routing-Table), from 4.4.4.4, 00:16:30 ago
Route metric is 409600, traffic share count is 1
AS Hops 0

R4(config)#int f0/1
R4(config-if)#delay 16777215

R2#sh ip route vrf v 5.5.5.0
Routing entry for 5.5.5.0/24
Known via “eigrp 1″, distance 90, metric 2323456, type internal
Redistributing via eigrp 1, bgp 234
Advertised by bgp 234
Last update from 10.1.12.1 on FastEthernet0/0, 00:00:01 ago
Routing Descriptor Blocks:
* 10.1.12.1, from 10.1.12.1, 00:00:01 ago, via FastEthernet0/0
Route metric is 2323456, traffic share count is 1
Total delay is 26000 microseconds, minimum bandwidth is 1544 Kbit
Reliability 255/255, minimum MTU 1500 bytes
Loading 1/255, Hops 2

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