NSX, ACI, OSPF, BGP single network easy, right?
Overview:
Two pod VVD design with an underlay built on Cisco ACI and using OSPF adjacencies with a single area with BGP providing adjacencies for the overlay provided by NSX.
Problem description: Inconsistent routing of traffic on the overlay.
The root of the Problem:
Edge-1 was publishing routes to ACI fabric to allowing underlay to route traffic to overlay networks. ACI was then publishing those routes to Edge-2 with higher priority than what the DLR was publishing the routes to Edge-2 as this causing traffic on Edge-2 could not forward to the DLR connected to Edge-2.
Resolution: Was to change the design from uplinks on multiple edges to uplink on single EDGE with HA enabled.
Reconfiguration:
Edge Configuration: Uplink to vDS and Internal connection to Global Transport Network
OSPF routing on EDGE: Uplink1 will connect to ToR for OSPF traffic.
BGP routing on EDGE: Configure Neighbors.
Route Distribution on EDGE: Needs two distributions from BGP to OSPF and accept all BGP.
DLR configuration: Uplink to EDGE-01 with three local virtual switches.
OSPF Configuration on DLR: Disable
BGP Configuration on the DLR: BGP connection to the Edge.
Route redistribution: Only BGP connected needed.
Final configuration architecture: