Symptom

SDA setup with 2 Anywhere Borders running multicast. Per vrf IBGP peering configured betweeen Anycast Borders. Multicast source and RP are outside fabric(on Fusion router) and learned via bgp more specific or default route on Border. Both Border's point the RPF for RP towards each other instead of Border handoff vlan causing multicast traffic blackhole. RP in output below is 192.168.X.X and is reachable via Vlan3003. D2-FB2#sh ip mroute vrf D2_VN1 224.Y.Y.Y (*, 224.Y.Y.Y), 13:02:41/00:03:04, RP 192.168.X.X, flags: S Incoming interface: LISP0.4099, RPF nbr 192.168.Y.Y <<<<<<<<<<<<<<<<<<<< pointing to other Border Outgoing interface list: LISP0.4099, 192.168.0.Z, Forward/Sparse, 13:00:28/00:02:40 LISP0.4099, 192.168.0.W, Forward/Sparse, 13:00:53/00:03:04 D2-FB2#sh ip rpf vrf D2_VN1 192.168.X.X RPF information for ? (192.168.X.X) RPF interface: LISP0.4099 <<<<<<<<<<<<<<<<<<<< wrong interface RPF neighbor: ? (192.168.0.U)<<<<<<<<<<<<<<<<<<<< pointing to other Border RPF route/mask: 192.168.X.X/32 RPF type: unicast () RIB, CEF and PD have correct interface towards RP. D2-FB2#sh ip route vrf D2_VN1 192.168.X.X Routing Table: D2_VN1 Routing entry for 192.168.X.X/32 Known via "bgp 65000", distance 20, metric 0 Tag 65002, type external Redistributing via lisp Last update from 192.168.V.V 09:44:17 ago Routing Descriptor Blocks: * 192.168.V.V, from 192.168.V.V, 09:44:17 ago D2-FB2#sh ip cef vrf D2_VN1 192.168.X.X 192.168.X.X/32 nexthop 192.168.V.V Vlan3003 D2-FB2#sh platform software fed switch active ip route vrf-name D2_VN1 192.168.X.X/32 3 192.168.X.X/32 0x7fdfcd7447e8 0x0 0 0 2020/07/07 03:43:10.812 FIB: prefix_hdl:0x6d0000a1, mpls_ecr_prefix_hdl:0 ========== OCE chain ===== ADJ:objid:91 {link_type:IP ifnum:0x90, si:0x7b000047, IPv4: 192.168.V.V }

Conditions

2 Anywhere Border running per vrf IBGP peering. Issue not seen with External border.

Workaround

Configure static route to RP on both Borders. D2-FB2(config)#ip route vrf D2_VN1 192.168.X.X 255.255.255.255 192.168.V.V D2-FB2(config)#do sh ip rpf vrf D2_VN1 192.168.X.X RPF information for ? (192.168.X.X) RPF interface: Vlan3003 RPF neighbor: ? (192.168.V.V) RPF route/mask: 192.168.X.X/32 RPF type: unicast (static) Doing distance-preferred lookups across tables RPF topology: ipv4 multicast base, originated from ipv4 unicast base D2-FB2(config)#do sh ip mroute vrf D2_VN1 (*, 224.Y.Y.Y), 00:02:38/00:02:49, RP 192.168.X.X, flags: S Incoming interface: Vlan3003, RPF nbr 192.168.V.V Outgoing interface list: LISP0.4099, 192.168.0.Z, Forward/Sparse, 00:01:49/00:02:40 LISP0.4099, 192.168.0.W, Forward/Sparse, 00:02:38/00:02:49

Further Problem Description