When port mirroring the same traffic flow twice (mirroring under family INET and under family VPLS), separate port-mirror instances are required. Inheriting instance parameters will result in "unexpected behavior" when they are applied to the same traffic flow.
This behavior is demonstrated in the article with the help of an example.
Port mirroring the same traffic flow under family INET and under family VPLS with the same instance
chassis { fpc 4 { pic 0 { tunnel-services { bandwidth 1g; } } port-mirror-instance inst1; } } interfaces { ge-4/0/1 { <<<--- Mirrored interface for family VPLS flexible-vlan-tagging; encapsulation flexible-ethernet-services; unit 23 { encapsulation vlan-vpls; vlan-id 23; } } ge-4/0/8 { <<<--- Mirrored interface for family inet unit 0 { family inet { address 192.168.0.2/30 { arp 192.168.0.1 mac 60:eb:69:0b:6c:56; } } } } ge-4/1/1 { <<<--- Called under Routing-Instance abc flexible-vlan-tagging; encapsulation flexible-ethernet-services; unit 530 { encapsulation vlan-vpls; vlan-id 530; family vpls; } } irb { <<<--- Called under Routing-Instance abc unit 530 { family inet { filter { input mirror_inet; output mirror_inet; } address 10.58.147.155/29; } } } } forwarding-options { port-mirroring { instance { inst1 { input { rate 1; run-length 1; } family inet { output { interface ge-4/0/8.0 { next-hop 192.168.0.1; } no-filter-check; } } } inst2 { input-parameters-instance PM; <<<--- Child instance inheriting parameters from Parent instance inst1. family vpls { output { interface ge-4/0/1.23; no-filter-check; } } } } } } firewall { family inet { filter mirror_inet { term 1 { then { count count; port-mirror-instance inst1; accept; } } term 2 { then accept; } } } family vpls { filter mirror_vpls { term 1 { then { count mirror; accept; port-mirror-instance inst2; } } } } } routing-instances { abc { instance-type vpls; vlan-id 530; interface ge-4/1/1.530; routing-interface irb.530; route-distinguisher 10.200.15.33:1111; vrf-target target:2222:1111; forwarding-options { family vpls { filter { input mirror_vpls; } flood { input mirror_vpls; } } } protocols { vpls { no-tunnel-services; site OBR-MX-2 { site-identifier 2; interface ge-4/1/1.530; } } } } xyz { instance-type vpls; vlan-id 23; interface ge-4/0/1.23; route-distinguisher 10.200.15.32:22; vrf-target target:2222:22; } } Interface: ge-4/0/1.23, Enabled, Link is Up Flags: SNMP-Traps 0x4000 Encapsulation: VLAN-VPLS VLAN-Tag [ 0x8100.23 ] Local statistics: Current delta Input bytes: 0 [0] Output bytes: 0 [0] Input packets: 0 [0] Output packets: 0 [0] Remote statistics: Input bytes: 0 (0 bps) [0] Output bytes: 51466626 (0 bps) [0] <<<--- VPLS port mirror fails. Input packets: 0 (0 pps) [0] Output packets: 504576 (0 pps) [0] Traffic statistics: Input bytes: 0 [0] Output bytes: 51466626 [0] Input packets: 0 [0] Output packets: 504576 [0] Interface: ge-4/0/8.0, Enabled, Link is Up Flags: SNMP-Traps 0x4004000 Encapsulation: ENET2 Local statistics: Current delta Input bytes: 0 [0] Output bytes: 0 [0] Input packets: 0 [0] Output packets: 0 [0] Remote statistics: Input bytes: 0 (0 bps) [0] Output bytes: 86044644 (344040 bps) [171024] <<<--- Inet has no issues. Input packets: 0 (0 pps) [0] Output packets: 1024341 (511 pps) [2036] Traffic statistics: Input bytes: 0 [0] Output bytes: 86044644 [171024] Input packets: 0 [0] Output packets: 1024341 [2036]
Port mirroring configured under family INET and under family VPLS with individual instances for each
chassis { fpc 4 { pic 0 { tunnel-services { bandwidth 1g; } } port-mirror-instance inst1; port-mirror-instance inst2; <<<---Another instance required for VPLS } } forwarding-options { port-mirroring { instance { inst1 { input { rate 1; run-length 1; } family inet { output { interface ge-4/0/8.0 { next-hop 192.168.0.1; } no-filter-check; } } } inst2 { <<<---Separate instance for family VPLS input { rate 1; run-length 1; } family vpls { output { interface ge-4/0/1.23; no-filter-check; } } } } } } Interface: ge-4/0/8.0, Enabled, Link is Up Flags: SNMP-Traps 0x4004000 Encapsulation: ENET2 Local statistics: Current delta Input bytes: 0 [0] Output bytes: 0 [0] Input packets: 0 [0] Output packets: 0 [0] Remote statistics: Input bytes: 0 (0 bps) [0] Output bytes: 767844168 (344040 bps) [0] <<<--- Family inet port mirror works. Input packets: 0 (0 pps) [0] Output packets: 9141002 (511 pps) [0] Traffic statistics: Input bytes: 0 [0] Output bytes: 767844168 [0] Input packets: 0 [0] Output packets: 9141002 [0] Protocol: inet, MTU: 1500, Flags: None Interface: ge-4/0/1.23, Enabled, Link is Up Flags: SNMP-Traps 0x4000 Encapsulation: VLAN-VPLS VLAN-Tag [ 0x8100.23 ] Local statistics: Current delta Input bytes: 0 [0] Output bytes: 0 [0] Input packets: 0 [0] Output packets: 0 [0] Remote statistics: Input bytes: 0 (0 bps) [0] Output bytes: 465980334 (208880 bps) [51918] <<<--- Family vpls port mirror works. Input packets: 0 (0 pps) [0] Output packets: 4569126 (255 pps) [509] Traffic statistics: Input bytes: 0 [0] Output bytes: 465980334 [51918] Input packets: 0 [0] Output packets: 4569126 [509]
2020-08-06: Article reviewed for accuracy; no changes made; article valid and relevant.2022-12-05: Updated non-compliant IP addresses to RFC standards.