You can also use the filter mechanism for IS-IS accept policies to redistribute routes between different VRFs, or between a VRF and the GRT. For inter-VRF route redistribution, you match the filter based on the I-SID, which represents the Layer 3 VSN context.
You can apply the filter at the global default level, where the IS-IS accept policy applies to all routes for that I-SID from all BEBs, or at a specific advertising BEB level, where the filter only applies to a specific advertising BEB. The device gives preference to a specific filter for a specific advertising BEB over the global default filter.
For inter-VRF route redistribution, an I-SID value of 0 represents the GRT. For inter-VRF route redistribution between VRFs, the I-SID is the source VRF (or remote VRF).
Note
If the primary B-VLAN is down either because you did not configure at least one network-to-network interface (NNI) or all configured NNIs are down, the switch does not redistribute inter-VRF routes through IS-IS accept policies.