Description
The article explains how to bring up LACP between two indirectly connected devices using Layer2-Protocol tunneling configuration.
Juniper Networks Ethernet switches and routers use Layer 2 protocol tunneling (L2PT) to send Layer 2 protocol data units (PDUs) across the network and deliver them to devices that are not part of the local broadcast domain.
This feature is useful when you want to run Layer 2 protocols on a network that includes switches located at remote sites that are connected across a service provider network.
L2PT works by encapsulating Layer 2 PDUs, tunneling them across a service provider network, and decapsulating them for delivery to their destination switches.
Symptoms
WORKING LAB EXAMPLE :
We want to bring the LACP up between the below MX240 and QFX10002 with a single device/multiple devices connected in between.
MX240(xe-1/0/0)--------(xe-0/0/0) EX4650 (xe-0/0/4)---------(xe-0/0/0:0)QFX10002
Here
MX240 and QFX10002
are the
end devices
between which the LACP/LLDP or any layer2 protocol needs to come up.
The
EX4650
device is acting as a
pure transit device
in between and should pass the LACP/LLDP packet as it is to the other end without dropping it.
Solution
Below is the configuration example to achieve this.
MX240 configuration - End device
set interfaces xe-1/0/0 gigether-options 802.3ad ae0
set interfaces ae0 aggregated-ether-options lacp active
set interfaces ae0 aggregated-ether-options lacp periodic fast
set interfaces ae0 aggregated-ether-options lacp system-id 00:00:00:00:00:11
set interfaces ae0 unit 0 family inet address 10.10.10.1/24
set protocols lldp interface all
QFX10002- configuration - End device
set interfaces xe-0/0/0:0 ether-options 802.3ad ae0
set interfaces ae0 aggregated-ether-options lacp active
set interfaces ae0 aggregated-ether-options lacp periodic fast
set interfaces ae0 aggregated-ether-options lacp system-id 00:00:00:00:00:22
set interfaces ae0 unit 0 family inet address 10.10.10.2/24
set protocols lldp interface all
You must configure and enable Q-in-Q tunneling (802.1Q VLAN encapsulation) on the transit device before you can configure L2PT.
EX4650 configuration - Transit device
Interfaces connected to UNI (User-to-network interface)
set interfaces xe-0/0/0 flexible-vlan-tagging
set interfaces xe-0/0/0 native-vlan-id 10
set interfaces xe-0/0/0 encapsulation extended-vlan-bridge
set interfaces xe-0/0/0 unit 0 vlan-id 10
set interfaces xe-0/0/0 unit 0 input-vlan-map push
set interfaces xe-0/0/0 unit 0 output-vlan-map pop
set interfaces xe-0/0/4 flexible-vlan-tagging
set interfaces xe-0/0/4 native-vlan-id 10
set interfaces xe-0/0/4 encapsulation extended-vlan-bridge
set interfaces xe-0/0/4 unit 0 vlan-id 10
set interfaces xe-0/0/4 unit 0 input-vlan-map push
set interfaces xe-0/0/4 unit 0 output-vlan-map pop
set vlans v10 interface xe-0/0/0.0
set vlans v10 interface xe-0/0/4.0
To configure L2PT on a specified interface:
set protocols layer2-control mac-rewrite interface xe-0/0/0 protocol lacp
set protocols layer2-control mac-rewrite interface xe-0/0/0 protocol lldp
set protocols layer2-control mac-rewrite interface xe-0/0/4 protocol lacp
set protocols layer2-control mac-rewrite interface xe-0/0/4 protocol lldp
Note : If there are multiple intermediate devices, you can configure the interfaces in a similar way as mentioned above for EX4650.
Lab Outputs:
MX240 shows LACP up and in CD state.
labroot@mx-240# run show lacp interfaces
Aggregated interface: ae0
LACP state: Role Exp Def Dist Col Syn Aggr Timeout Activity
xe-1/0/0 Actor No No Yes Yes Yes Yes Fast Active
xe-1/0/0 Partner No No Yes Yes Yes Yes Fast Active
LACP protocol: Receive State Transmit State Mux State
xe-1/0/0 Current Fast periodic Collecting distributing
QFX10002 shows LACP up and in CD state.
root@qfx10002# run show lacp interfaces
Aggregated interface: ae0
LACP state: Role Exp Def Dist Col Syn Aggr Timeout Activity
xe-0/0/0:0 Actor No No Yes Yes Yes Yes Fast Active
xe-0/0/0:0 Partner No No Yes Yes Yes Yes Fast Active
LACP protocol: Receive State Transmit State Mux State
xe-0/0/0:0 Current Fast periodic Collecting distributing
QFX10002 showing MX240 as it's LLDP neighbor.
root@
qfx10002
# run show lldp neighbors
Local Interface Parent Interface Chassis Id Port info System Name
xe-0/0/0:0 ae0 f0:4b:3a:4d:18:00 xe-1/0/0 mx-240
To verify if the ping is working fine and if the traffic is flowing bi-directional.
labroot@mx-240# run ping 10.10.10.2
PING 10.10.10.2 (10.10.10.2): 56 data bytes
64 bytes from 10.10.10.2: icmp_seq=15 ttl=64 time=1.810 ms
64 bytes from 10.10.10.2: icmp_seq=16 ttl=64 time=1.858 ms
64 bytes from 10.10.10.2: icmp_seq=17 ttl=64 time=1.929 ms
root@qfx10002# run monitor traffic interface xe-0/0/0:0 no-resolve
verbose output suppressed, use <detail> or <extensive> for full protocol decode
Address resolution is OFF.
Listening on xe-0/0/0:0, capture size 96 bytes
18:55:50.295957 Out IP truncated-ip - 24 bytes missing! 10.10.10.2 > 10.10.10.1: ICMP echo reply, id 13359, seq 15, length 64
18:55:51.305383 Out IP truncated-ip - 24 bytes missing! 10.10.10.2 > 10.10.10.1: ICMP echo reply, id 13359, seq 16, length 64
18:55:52.306336 Out IP truncated-ip - 24 bytes missing! 10.10.10.2 > 10.10.10.1: ICMP echo reply, id 13359, seq 17, length 64
Modification History
2023-06-16 - Minor formatting
2024-07-29 - Visibility modified
LACP/LLDP between two devices with a transit device in between using Layer2 Protocol Tunneling