Configuring Cisco ACI to Accept More Routes From the IPN
When routes are advertised to the physical spines from the interpod network (IPN), Open Shortest Path First (OSPF) restributes those routes only to Intermediate System to Intermediate System (IS-IS). This redistribution happens when IS-IS is part of an existing tunnel endpoint (TEP) pool or part of a subnet that is configured under Fabric Ext Connection Policies in the Cisco Application Policy Infrastructure Controller (APIC).
Because of this behavior, spines that are not connected to the IPN cannot reach the vSpines. If your data plane TEP and vSpine router IDs are not part of the Cisco Application Centric Infrastructure (ACI) Virtual Pod (vPod) TEP pool, you must configure the Fabric Ext Connection Policies with those subnets.
Configure the router ID, the data plane (TEP), or both for the vSpine and Cisco ACI vPod as a secondary route on the IPN.
Log in to Cisco APIC.
Under the configured policy, add the subnets to the Fabric External Routing Profile.