VPLS connects to JP, and the terminal under the AC port cannot learn the remote ARP

As following:

Access SWs connected to our side 5590 and the opposite Jp cannot learn the remote ARP. The vsi and pw states are up on both sides of the PE and can learn the L2vpn mac of both ends.

1. Check the configuration and entries at both sides: The data encapsulation type of both PW is Ethernet, the status of PW and vsi are UP on both sides, and PEs can learn the remote l2vpn mac address.

S5590 configuration:

#

pw-class Port

control-word enable

pw-type ethernet

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vsi 5

mtu 9000

pwsignaling ldp

  peer 101.96.86.240 pw-id 50111 pw-class Port

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interface GigabitEthernet1/0/25

port link-mode bridge

port link-type trunk

port trunk permit vlan all

combo enable fiber

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service-instance 10

  encapsulation s-vid 250

  xconnect vsi 5

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Juniper MX204 configuration:

set routing-instances H-VPLS-TEST instance-type vpls

set routing-instances H-VPLS-TEST protocols vpls mesh-group xxx-TEST neighbor 10.x.x.142 pseudowire-status-tly

set routing-instances H-VPLS-TEST protocols vpls encapsulation-type ethernet

set routing-instances H-VPLS-TEST protocols vpls no-tunnel-services

set routing-instances H-VPLS-TEST protocols vpls vpls-id 50111

set routing-instances H-VPLS-TEST protocols vpls mtu 9000

set routing-instances H-VPLS-TEST vlan-id 250

set routing-instances H-VPLS-TEST interface ae30.3201

set interfaces ae30 unit 3201 encapsulation vlan-vpls

set interfaces ae30 unit 3201 vlan-id 250

set interfaces ae30 unit 3201 family vpls

2. Confirm whether the ARP from the AC port is sent out normally through VPLS encapsulation.

①Firstly, try to apply qos policy to do traffic statistics by remarking packets. The traffic statistics results are as follows: the outbound direction of XG1/0/30 cannot be counted for the dot1p, which is remarked inbound of the AC port.

②Make a port mirroring to capture packets. MPLS was reset once halfway, and the PW label was changed to in label: 131199, out label: 410.

H3C"s PW Ethernet encapsulation does not carry tag in mechanism. From the packet capture, it seems that the Juniper side is not using this mechanism, as it still carries tag after encapsulation.

When the PW data encapsulation type is Ethernet, P-tag is not transferred on a PW.

·     For a packet from a CE:

¡     If the packet contains a P-tag, the PE removes the P-tag, and adds a PW label and an outer tag into the packet before forwarding it.

¡     If the packet contains no P-tag, the PE directly adds a PW label and an outer tag into the packet before forwarding it.

You cannot rewrite or remove existing tags.

③Capture the ARP packet on the Access SW side and found that the received ARP packet carries two layers of tags, with both svid and cvid being 250, which caused the device to fail to learn ARP normally.

·     For a packet to a CE:

¡     If the access mode is configured as VLAN by using the ac interface command, the PE adds a P-tag into the packet before sending it to the CE.

¡     If the access mode is configured as Ethernet by using the ac interface command, the PE directly sends the packet to the CE.

To be compatible with Juniper switch PW encapsulation, we need to modify the AC port access mode to Ethernet without adding additional tags for forwarding to the CE device.

#

interface GigabitEthernet1/0/25

port link-mode bridge

port link-type trunk

port trunk permit vlan all

combo enable fiber

#

service-instance 10

  encapsulation s-vid 250

  xconnect vsi 5 access-mode ethernet

#

 To be compatible with JP switch PW encapsulation, we need to modify the AC port access mode to Ethernet without adding additional tags for forwarding to the CE device.

#

interface GigabitEthernet1/0/25

port link-mode bridge

port link-type trunk

port trunk permit vlan all

combo enable fiber

#

service-instance 10

  encapsulation s-vid 250

  xconnect vsi 5 access-mode ethernet

#