Techniques for using global virtual network instance (VNI) labels in a multi-domain network to route network data with a multi-tenant network overlay are described herein. A routing device provisioned in a network domain of the multi-domain network may register with a service discovery system of the network domain for use of network configuration data to establish routes through the multi-domain network with network nodes. Each network domain of the multi-domain network may include an application programming interface (API) server for processing API requests to make changes to configurations of a network domain. A border gateway protocol (BGP) large community may be utilized to encode global VNI labels, network addresses, local next hop nodes, and/or additional network information and sent to routing devices provisioned in separate network domains. A service chain may be signaled by global VNI labels to route network traffic through various services prior to reaching a destination endpoint.