For VPRN, EVPN-VPLS, and EVPN-VPWS, routes may be imported via peer route import policies that contain route admin-tag policies or via VRF import for VPRN and VSI import for E-VPN VPLS used for auto-bind-tunnel.
VRF import and VSI import policies take precedence over the peer route import policy.
For policies that contain route admin-tag policies, the set of available RSVP and SR-TE LSPs in TTM are first pruned as described in Internal Route Color to LSP Color Matching Algorithm. This set may then be further reduced by a resolution filter. If weighted-ecmp is configured, then this is applied across the resulting set.
Routes with no admin-tag, or a tag that is not explicitly excluded by the route admin tag policy, can still resolve to any tagged or untagged LSP but matching tagged LSPs are used in preference to any other. It is possible that following the resolution filter no eligible RSVP or SR-TE LSP exists. By default, the system falls back to regular auto-bind behavior using LDP, SR-ISIS, SR-OSPF, or any other lower priority configured tunnel type, otherwise the resolution fails. That is, matching admin-tagged RSVP or SR-TE LSPs are used in preference to other LSP types, whether tagged or untagged. However, it is possible on a per-service basis to enforce that only specific tagged tunnels should be considered, otherwise resolution fails, using the enforce-strict-tunnel-tagging command in the auto-bind-tunnel context.
For E-VPN VPWS, VSI import is not supported. Therefore, admin-tag policies can only be applied via a peer route import policy based on a match on the route target for the BGP peer for the VPWS.