We are experiencing issues with single VLAN DHCP over VPLS not working on JUNOS 21.4R3-S6.5. We did a rollback to the previous version to resolve this. No changes was made to the config. Uploading RSI & logs. If further tests are needed on the ACX, we could schedule an upgrade in a maintenance window.
Traffic expecting untagged packets over CCC/VPLS/L2Circuit got tagged on ACX710 egress ports. Customer has interface configure as below:
xe-0/0/3 { flexible-vlan-tagging; mtu 9192; encapsulation flexible-ethernet-services; unit 60 { encapsulation vlan-vpls; vlan-id 60; input-vlan-map pop; <<<<<<<<<<< output-vlan-map push; <<<<<<<<< family vpls; } }
When do a packet capture between ACX710 and the peer device, an additional VLAN tag can be seen. For example, below is capture on the peer MX router.
Wallclock: b6fdde8f Received 270 byte parcel: Dispatch cookie: 010e000000000000 10 09 c0 f0 01 57 83 08 3c 8a b0 8c d4 4a 1c 90 be 08 12 85 81 00 00 64 88 47 49 39 02 ff 40 00 33 ff ff ff ff ff ff ff <<<<<<<< paylod start from here 00 51 6a fc 00 00 81 00 <<<<<< 0x8100 0000 ---> VLAN_ID 0 00 00 08 00 45 00 01 2d 00 00 40 00 40 11 39 c1 00 00 00 00 ff ff ff ff 00 44 00 43 01 19 e1 44 01 01 06 00 4e 7d 4a a7 00 00 80 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 6a fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
With the same confiugre but JUNOS 20.4, the working packet as this.
Wallclock: b6fdde8f Received 270 byte parcel: Dispatch cookie: 010e000000000000 10 09 c0 f0 01 57 83 08 3c 8a b0 8c d4 4a 1c 90 be 08 12 85 81 00 00 64 88 47 49 3a 02 ff 40 00 33 ff ff ff ff ff ff ff <<<<<<<<<< payload starts here 00 51 6a fc 00 00 08 00 <<<<<there has no VLAN-ID here. 45 00 01 2d 00 00 40 00 40 11 39 c1 00 00 00 00 ff ff ff ff 00 44 00 43 01 19 24 18 01 01 06 00 1b c9 3a 88 00 00 80 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 6a fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
The problem is caused by the side effect of PR1633395 fix. PR1789949 has fixed this issue.