OPERATIONAL DEFECT DATABASE
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a loop is created in one of the PEs adding a static route pointing to a route that is beyond the second PE when the static route is remove is when we are seeing the xconnect is no longer passing traffic from the CEs when is working the programming PE1#sh mpls forwarding-table Local Outgoing Prefix Bytes Label Outgoing Next Hop Label Label or Tunnel Id Switched interface 16 16 192.168.100.0/24 0 Vl10 192.168.1.2 17 No Label l2ckt(2) 2855156 Twe1/0/23 point2point 20 explicit-n 10.0.0.2/32 40117 Vl10 192.168.1.2 PE1#sh mpls l2 vc 10 det Local interface: Twe1/0/23 up, line protocol up, Ethernet up Destination address: 10.0.0.2, VC ID: 10, VC status: up Output interface: Vl10, imposed label stack {0 18} Preferred path: not configured Default path: active Next hop: 192.168.1.2 MPLS VC labels: local 17, remote 18 Group ID: local n/a, remote 0 MTU: local 1500, remote 1500 Remote interface description: Sequencing: receive disabled, send disabled Control Word: On (configured: autosense) SSO Descriptor: 10.0.0.2/10, local label: 17 Dataplane: SSM segment/switch IDs: 4102/4101 (used), PWID: 2 VC statistics: transit packet totals: receive 25386, send 93042 transit byte totals: receive 2855156, send 6642528 transit packet drops: receive 0, seq error 0, send 0 at the PW we are seeing the labels that belongs to the remote PE and the transport label same on the programming on the imposition label 20 for the transport label and 18 for the remote PE label ATOM_IMP:121 pw_label:18 grand_parent_local_label:20 drop_flag:0 pw_id: 2 imp_flags:0x1 pdflags:0 hw_handle:0x8d000002 imp_flags (FED) in detail CW AAL: id:2365587458 pw_label:18 grand_parent_local_label:20 adj_flags:0x4 ref_cnt:1 adj_flags in detail: TYPE4 VC/PORT MODE CW Enabled port_hdl:0, port_id:0, drop_adj_flag:0 is_vfi_seg:0 sph_id:0 stats_valid:1 defer_del:(nil) defer_del_ri:0 when the loop happens we are seeing the new entry we are still having out transport label as 20 and our PW label as 18 PE1#sh mpls forwarding-table Local Outgoing Prefix Bytes Label Outgoing Next Hop Label Label or Tunnel Id Switched interface 16 16 192.168.100.0/24 0 Vl10 192.168.1.2 17 No Label l2ckt(2) 2855156 Twe1/0/23 point2point 19 explicit-n 192.168.100.10/32 \ 60020 Vl10 192.168.1.2 >>>> new entry creating the loop 20 explicit-n 10.0.0.2/32 60020 Vl10 192.168.1.2 at the PW imp label we are seeing that this changed to 19 my transport the same that I have with the route 192.168.100.10 ATOM_XCAC:94 ac_type:1 ac_ifh:94, iw_type:1 pw_lb_mode:0 if_h:94, if_type:0 peer_addr:167772162(10.0.0.2) remote_gid:0 flags:0 pdflags:0 ref_cnt:1 hw_handle:0 pw_ctx[pw_id,seg_status]: 0=[2, 1] 1=[0, 0] ATOM_IMP:121 pw_label:18 grand_parent_local_label:19 drop_flag:0 pw_id: 2 when we remove the static route the labels at the PW remains the same making that the traffic at the CE level drops PE1#sh mpls forwarding-table Local Outgoing Prefix Bytes Label Outgoing Next Hop Label Label or Tunnel Id Switched interface 16 16 192.168.100.0/24 0 Vl10 192.168.1.2 17 No Label l2ckt(2) 2855156 Twe1/0/23 point2point 19 No Label 192.168.100.10/32 \ 0 drop >>>> entry removed 20 explicit-n 10.0.0.2/32 70055 Vl10 192.168.1.2 ATOM_XCAC:94 ac_type:1 ac_ifh:94, iw_type:1 pw_lb_mode:0 if_h:94, if_type:0 peer_addr:167772162(10.0.0.2) remote_gid:0 flags:0 pdflags:0 ref_cnt:1 hw_handle:0 pw_ctx[pw_id,seg_status]: 0=[2, 1] 1=[0, 0] ATOM_IMP:121 pw_label:18 grand_parent_local_label:19 drop_flag:0 pw_id: 2 >>> getting the imp label 19 same as the entry 192.168.100.10/32
loop created on the network adding static and remove it after this the xconnect stops to forwarding traffic
clearing the IGP fix the problem and reprogram the imp label
MPLS label mismatch after a loop | xconnect being affected and not passing traffic
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