I have 3 data centers spread across 2 different companies.
2 are in the same building separated by a wall (Data Center A and Data Center B)
1 is in a different state (Data Center C)
Data Center A and C belong to the same company, are part of the same domain and are connected via MPLS.
Data Center B is a different company and different domain.
There is a trust between the two domains. Datacenter B can communicate with Data Center A as there is a direct connection between the two L3 switches.
I want to set up communication between Data Center B and C using the MPLS connection between A and C
I am not sure how I need to set that up. I had hoped all I would need to do was set up the vlan and add routing to DataCenter B. This is not the case.