Description

Sending tagged and untagged or dual tagged traffic packets over an untagged interface towards CE1 in L2circuit/VPWS termination flow In device Ex4650 (td 3) is not supported as it is in EX4600's and QFX5100's (td 2). This is a hardware limitation.

Symptoms

Topology

CE1--PE1--P--PE2--CE2

PE1 router 

set interfaces ae0 unit 123 description VLAN123
set interfaces ae0 unit 123 vlan-id 123 ----> tagged
set interfaces ae0 unit 123 family inet address 1.2.3.2/30
set interfaces ae0 unit 123 family mpls

set interfaces ge-0/0/10 description TO_CE1
set interfaces ge-0/0/10 encapsulation ethernet-ccc
set interfaces ge-0/0/10 unit 0 family ccc ----> untagged

P router 

set interfaces ae0 unit 123 description VLAN123
set interfaces ae0 unit 123 vlan-id 123 ----> tagged
set interfaces ae0 unit 123 family inet address 1.2.3.1/30
set interfaces ae0 unit 123 family mpls

Here uplink (PE <--> P) is tagged l3 interface and (CE <-> PE) is untagged l2 interface having family ccc. PE1 (EX4650) won't be able to forward inner tagged L2 packet received from P device towards CE1 end points as part of L2circuit/VPWS termination flow.

Tagged Ping from CE1 to CE2 will not work: 

{master:0}[edit]
root@CE1# run ping 10.26.2.2 source 10.26.2.1                  
PING 10.26.2.2 (10.26.2.2): 56 data bytes

Solution

Configure the L3 inteface on the PE1 router and the P router as untagged to match the TO_CE1 interface 

PE1 router 

set interfaces ge-0/0/10 description TO_CE1
set interfaces ge-0/0/10 encapsulation ethernet-ccc
set interfaces ge-0/0/10 unit 0 family ccc ----> untagged
PE1 router
set interfaces ae10 unit 0 family inet address 1.2.3.2/30 ----> untagged
set  interfaces ae10 unit 0 family mpls

P router 

set interfaces ae10 unit 0 family inet address 1.2.3.1/30 ----> untagged
set interfaces ae10 unit 0 family mpls

root@CE1# run ping 10.26.2.2 source 10.26.2.1
PING 10.26.2.2 (10.26.2.2): 56 data bytes
64 bytes from 10.26.2.2: icmp_seq=0 ttl=64 time=3.297 ms
64 bytes from 10.26.2.2: icmp_seq=1 ttl=64 time=3.239 ms
64 bytes from 10.26.2.2: icmp_seq=2 ttl=64 time=2.163 ms
64 bytes from 10.26.2.2: icmp_seq=3 ttl=64 time=2.165 ms
64 bytes from 10.26.2.2: icmp_seq=4 ttl=64 time=3.166 ms