Example for Configuring a Basic MLAG
- Tracy Yang
- Seren.tian
- Arale Li
Networking Requirements
Figure 1. Basic MLAG Topology
In Figure 1, SwitchB dual accesses the network through SwitchA1 and SwitchA2 using LACP LAG.
At first, SwitchB accesses the network through SwitchA1. If SwitchA1 or the link between SwitchB and SwitchA1 fails, SwitchB cannot communicate with the network. To avoid service interruptions, we can configure MLAG on SwitchA1 and SwitchA2. When communication between SwitchB and SwitchA1 fails, traffic from the SwitchB will be switched to SwitchA2 seamlessly. When SwitchA1 or the link between SwitchB and SwitchA1 recovers, traffic from the SwitchB will be switched back to SwitchA1.
The peer link between SwitchA1 and SwitchA2 is configured to carry MLAG related control traffic and is very critical to the operation of MLAG function.
Procedure
SwitchA1
Step1 Configure the VLANs.
admin@SwitchA1# set vlans vlan-id 15
admin@SwitchA1# set vlans vlan-id 16
admin@SwitchA1# set vlans vlan-id 4088 l3-interface vlan4088
admin@SwitchA1# set interface aggregate-ethernet ae1 family ethernet-switching port-mode trunk
admin@SwitchA1# set interface aggregate-ethernet ae1 family ethernet-switching vlan members 15
admin@SwitchA1# set interface aggregate-ethernet ae1 family ethernet-switching vlan members 16
admin@SwitchA1# set interface aggregate-ethernet ae2 family ethernet-switching native-vlan-id 4088
admin@SwitchA1# set interface aggregate-ethernet ae2 family ethernet-switching port-mode trunk
admin@SwitchA1# set interface aggregate-ethernet ae2 family ethernet-switching vlan members 15
admin@SwitchA1# set interface aggregate-ethernet ae2 family ethernet-switching vlan members 16
Step2 Configure MLAG interfaces with LACP mode.
admin@SwitchA1# set interface aggregate-ethernet ae1 aggregated-ether-options lacp enable true
Step3 Add member interfaces to a LAG.
admin@SwitchA1# set interface gigabit-ethernet ge-1/1/1 ether-options 802.3ad ae1
admin@SwitchA1# set interface gigabit-ethernet te-1/1/49 ether-options 802.3ad ae2
admin@SwitchA1# set interface gigabit-ethernet te-1/1/50 ether-options 802.3ad ae2
Step4 Configure an MLAG domain ID.
admin@SwitchA1# set protocols mlag domain 10
NOTE: Currently, only one MLAG domain is allowed to be configured on one MLAG device.
Step5 Specify SwitchA1 as MLAG Node 0.
admin@SwitchA1# set protocols mlag domain 10 node 0
Step6 Configure the peer IP address and peer link port.
admin@SwitchA1# set protocols mlag domain 10 peer-ip 10.10.0.2 peer-link ae2
NOTE: Peer-link port should be configured as a LAG port.
Step7 Configure the L3 interface IP address for peer link port on local MLAG peer device.
admin@SwitchA1# set l3-interface vlan-interface vlan4088 address 10.10.0.1 prefix-length 24
Step8 Enable IP routing function when using basic MLAG.
admin@SwitchA1# set ip routing enable true
Step9 Configure link ID for the MLAG member port.
admin@SwitchA1# set protocols mlag domain 10 interface ae1 link 2
NOTE: The paired MLAG member ports must be bound to the same MLAG link ID.
Step10 Configure MLAG peer VLAN.
admin@SwitchA1# set protocols mlag domain 10 peer-ip 10.10.0.2 peer-vlan 4088
Step11 Commit the configuration.
admin@SwitchA1# commit
SwitchA2
The configuration on SwitchA2 is the same as SwitchA1.
Step1 Configure the VLANs.
admin@SwitchA2# set vlans vlan-id 15
admin@SwitchA2# set vlans vlan-id 16
admin@SwitchA2# set vlans vlan-id 4088 l3-interface vlan4088
admin@SwitchA2# set interface aggregate-ethernet ae1 family ethernet-switching port-mode trunk
admin@SwitchA2# set interface aggregate-ethernet ae1 family ethernet-switching vlan members 15
admin@SwitchA2# set interface aggregate-ethernet ae1 family ethernet-switching vlan members 16
admin@SwitchA2# set interface aggregate-ethernet ae2 family ethernet-switching native-vlan-id 4088
admin@SwitchA2# set interface aggregate-ethernet ae2 family ethernet-switching port-mode trunk
admin@SwitchA2# set interface aggregate-ethernet ae2 family ethernet-switching vlan members 15
admin@SwitchA2# set interface aggregate-ethernet ae2 family ethernet-switching vlan members 16
Step2 Configure MLAG interfaces with LACP mode.
admin@SwitchA2# set interface aggregate-ethernet ae1 aggregated-ether-options lacp enable true
Step3 Add member interfaces to a LAG.
admin@SwitchA2# set interface gigabit-ethernet ge-1/1/1 ether-options 802.3ad ae1
admin@SwitchA2# set interface gigabit-ethernet te-1/1/49 ether-options 802.3ad ae2
admin@SwitchA2# set interface gigabit-ethernet te-1/1/50 ether-options 802.3ad ae2
Step4 Configure an MLAG domain ID.
admin@SwitchA2# set protocols mlag domain 10
NOTE: Currently, only one MLAG domain is allowed to be configured on one MLAG device.
Step5 Specify SwitchA2 as MLAG Node 1.
admin@SwitchA2# set protocols mlag domain 10 node 1
Step6 Configure the peer IP address and peer link port.
admin@SwitchA2# set protocols mlag domain 10 peer-ip 10.10.0.1 peer-link ae2
NOTE: Peer-link port should be configured as a LAG port.
Step7 Configure the L3 interface IP address for peer link port on local MLAG peer device.
admin@SwitchA2# set l3-interface vlan-interface vlan4088 address 10.10.0.2 prefix-length 24
Step8 Enable IP routing function when using basic MLAG.
admin@SwitchA2# set ip routing enable true
Step9 Configure link ID for the MLAG member port.
admin@SwitchA2# set protocols mlag domain 10 interface ae1 link 2
Step10 Configure MLAG peer VLAN.
admin@SwitchA2# set protocols mlag domain 10 peer-ip 10.10.0.1 peer-vlan 4088
Step11 Commit the configuration.
admin@SwitchA2# commit
NOTE: The paired MLAG member ports must be bound to the same MLAG link ID.
SwitchB
Step1 Enable aggregation interface with LACP mode.
admin@SwitchB# set interface aggregate-ethernet ae1 aggregated-ether-options lacp enable true
Step2 Add member interfaces to a LAG.
admin@SwitchB# set interface gigabit-ethernet ge-1/1/1 ether-options 802.3ad ae1
admin@SwitchB# set interface gigabit-ethernet ge-1/1/2 ether-options 802.3ad ae1
Step3 Configure VLAN.
admin@SwitchB# set vlans vlan-id 15
admin@SwitchB# set vlans vlan-id 16
admin@SwitchB# set interface aggregate-ethernet ae1 family ethernet-switching port-mode trunk
admin@SwitchB# set interface aggregate-ethernet ae1 family ethernet-switching vlan members 15
admin@SwitchB# set interface aggregate-ethernet ae1 family ethernet-switching vlan members 16
Step4 Enable IP routing function when using basic MLAG.
admin@SwitcB# set ip routing enable true
Step5 Commit the configuration.
admin@SwitchB# commit
Verifying the Configuration
You can use the run show mlag domain command to display the global MLAG domain information.
admin@SwitchA1# run show mlag domain summary
Domain ID: 10 Domain MAC: 48:6E:73:FF:00:0a Node ID: 0
-----------------------------------------------------------------------
Peer Link Peer IP Peer Vlan Neighbor Status Config Matched MAC Synced # of Links
--------- --------------- --------- --------------- -------------- ---------- ----------
ae2 10.10.10.2 4088 ESTABLISHED Yes Yes 1 You can use the run show mlag link command to display MLAG link information.
admin@SwitchA1# run show mlag link summary
# of Links: 1
Link Local LAG Link Status Local Status Peer Status Config Matched Flood
---- --------- ----------- ------------ ----------- -------------- -----
2 ae1 IDLE UP UNKNOWN No NoYou can use the run show mlag consistency-parameter command to display the result of MLAG configuration consistency check, including the global and per MLAG configuration.
admin@SwitchA1# run show mlag consistency-parameter link 2
Port Configurations:
----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
MTU 1514 1514 PASS
Mac Learning Yes Yes PASS
Lag Mode LACP LACP PASS
Native Vlan 1 1 PASS
Port Vlan Mode Trunk Trunk PASS
Trunk Vlan Count 2 2 PASS
Trunk VLAN IDs PASS
Spanning-Tree Configurations:
-----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
Mode PASS
VXLAN Configurations:
-----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
Link 1 VXLAN N/A N/A FAIL
admin@SwitchA1# run show mlag consistency-parameter summary
Overall : PASS
--------------
Global : PASS
Link 2 : PASS
MLAG Configurations:
-----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
Domain ID 1 1 PASS
Node ID 0 1 PASS
Peer VLAN 4088 4088 PASS
Link Count 1 1 PASS
Link IDs 2 2 PASS
Spanning-Tree Configurations:
-----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
Enable No No PASS
DHCP Snooping Configurations:
-----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
VLAN Count 0 4 FAIL
VLAN IDs FAIL
IGMP Snooping Configurations:
-----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
Enable No No PASS
VXLAN Configurations:
-----------------------------------------------------------------
Property Local Value Peer Value Result
----------------------- --------------- --------------- ------
VXLAN N/A N/A PASS
VXLAN VNI Count 0 0 PASS
VXLAN VNIs PASSYou can use the run show lacp neighbor command to view the config information of LACP neighbor.
admin@SwitchA1# run show lacp neighbor
Aggregated interface: ae1
Port Number Partner System ID Partner Port Num Port Priority Admin Key Oper Key State
----------- ----------------------- ---------------- ------------- --------- -------- -----
ge-1/1/1 32768,08:9E:01:61:64:13 1 32768 0x00 0x35 0x3D
Aggregated interface: ae2
Port Number Partner System ID Partner Port Num Port Priority Admin Key Oper Key State
------------------------------------------------------------------------------------------------------------------
te-1/1/49 32768,70:72:CF:B7:60:A5 73 73 32768 0x00 0x50 0x3D
te-1/1/50 32768,70:72:CF:B7:60:A5 73 74 32768 0x00 0x50 0x3D
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