MLAG Active-Active Dynamic Configuration
MLAG (also called DRNI, Distributed Resilient Network Interconnect) expands the concept of link aggregation so that it provides node-level redundancy by allowing two or more nodes to share a common LAG endpoint. MLAG emulates multiple nodes to represent as a single logical node to the remote node running link aggregation. As a result, even if one of the nodes is down there exists a path to reach the destination through the other nodes.
Note: MLAG is compatible only with a RSTP VLAN-aware bridge or a spanning tree disabled bridge.
Note: All MLAG nodes must have the same MAC table size as specified by each node's switching ASIC forwarding profile limit.
Topology
As shown in Figure 13-29, TOR 1 and TOR 2 form an MLAG domain. TOR 1 and TOR 2 are a single logical switch to LEAF and LwSW. Even if either TOR 1 or TOR 2 is down, there exists a path to reach other destinations.
Figure 13-29: MLAG Active-Active Topology
LEAF
#configure terminal | Enter configure mode. |
(config)#hardware-profile filter egress-l2 enable | Enable the hardware-profile filter |
(config)#bridge 1 protocol rstp vlan-bridge | Create RSTP bridge 1. |
(config)#vlan 2 bridge 1 state enable | Create VLAN 2. |
(config)#interface po2 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#bridge-group 1 | Associate the interface with bridge group 1. |
(config-if)#switchport mode trunk | Set the switching characteristics of this interface to trunk mode. |
(config-if)#switchport trunk allowed vlan all | Enable all VLAN identifiers on this interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe1 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe2 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe33 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe34 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
LwSW
#configure terminal | Enter configure mode. |
(config)#hardware-profile filter egress-l2 enable | Enable the hardware-profile filter |
(config)#bridge 1 protocol rstp vlan-bridge | Create RSTP bridge 1. |
(config)#vlan 2 bridge 1 state enable | Create VLAN 2. |
(config)#interface po1 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#bridge-group 1 | Associate the interface with bridge group 1. |
(config-if)#switchport mode trunk | Set the switching characteristics of this interface to trunk mode. |
(config-if)#switchport trunk allowed vlan all | Enable all VLAN identifiers on this interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe5 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe6 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe7 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#exit | Exit interface mode. |
(config)#interface xe8 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
TOR-01
#configure terminal | Enter configure mode. |
(config)#hardware-profile filter egress-l2 enable | Enable the hardware-profile filter |
(config)#interface mlag1 | Enter interface mode. |
(config-if)#mode active-active | Mode need to be configured as active-active |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface mlag2 | Enable the hardware-profile filter |
(config-if)#mode active-active | Mode need to be configured as active-active |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#bridge 1 protocol rstp vlan-bridge | Create RSTP bridge 1. |
(config)#vlan 2 bridge 1 state enable | Create VLAN 2. |
(config)#interface mlag1 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#bridge-group 1 spanning-tree disable | Disable the spanning-tree for the interface |
(config-if)#switchport mode trunk | Set the switching characteristics of this interface to trunk mode. |
(config-if)#switchport trunk allowed vlan all | Enable all VLAN identifiers on this interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface mlag2 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#bridge-group 1 spanning-tree disable | Disable the spanning-tree for the interface |
(config-if)#switchport mode trunk | Set the switching characteristics of this interface to trunk mode. |
(config-if)#switchport trunk allowed vlan all | Enable all VLAN identifiers on this interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface po1 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#mlag 1 | Enabling MLAG group number |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface po2 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#mlag 2 | enabling Mlag group number |
(config-if)#exit | Exit interface mode. |
(config)#interface xe9 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe57 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe58 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe10 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe49 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#exit | Exit interface mode. |
(config)#mcec domain configuration | Entering MCEC mode |
(config-mcec-domain)#domain-address 1111.2222.3333 | Domain address for the mlag domain |
(config-mcec-domain)#intra-domain link xe49 | Intra domain line between mlag domain |
(config-mcec-domain)#domain-system-number 1 | Number to identify the node in a domain |
(config-mcec-domain)#commit | Commit the candidate configuration to the running configuration |
(config-mcec-domain)#exit | Exit MCEC mode |
TOR-02
#configure terminal | Enter configure mode. |
(config)#hardware-profile filter egress-l2 enable | Enable the hardware-profile filter |
(config)#interface mlag1 | Enter interface mode. |
(config-if)#mode active-active | Mode need to be configured as active-active |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode |
(config)#interface mlag2 | Enable the hardware-profile filter |
(config-if)#mode active-active | Mode need to be configured as active-active |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode |
(config)#bridge 1 protocol rstp vlan-bridge | Create RSTP bridge 1. |
(config)#vlan 2 bridge 1 state enable | Create VLAN 2. |
(config)#interface mlag1 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#bridge-group 1 spanning-tree disable | Disable the spanning-tree for the interface |
(config-if)#switchport mode trunk | Set the switching characteristics of this interface to trunk mode. |
(config-if)#switchport trunk allowed vlan all | Enable all VLAN identifiers on this interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode |
(config)#bridge 1 protocol rstp vlan-bridge | Create RSTP bridge 1. |
(config)#vlan 2 bridge 1 state enable | Create VLAN 2. |
(config)#interface mlag1 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#bridge-group 1 spanning-tree disable | Disable the spanning-tree for the interface |
(config-if)#switchport mode trunk | Set the switching characteristics of this interface to trunk mode. |
(config-if)#switchport trunk allowed vlan all | Enable all VLAN identifiers on this interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface mlag2 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#bridge-group 1 spanning-tree disable | Disable the spanning-tree for the interface |
(config-if)#switchport mode trunk | Set the switching characteristics of this interface to trunk mode. |
(config-if)#switchport trunk allowed vlan all | Enable all VLAN identifiers on this interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface po1 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#mlag 1 | Enabling Mlag group number |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface po2 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#mlag 2 | enabling MLAG group number |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe9 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe10 | Enter interface mode. |
(config-if)#channel-group 1 mode active | Add this interface to channel group 1 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe57 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe58 | Enter interface mode. |
(config-if)#channel-group 2 mode active | Add this interface to channel group 2 and enable link aggregation so that it can be selected for aggregation by the local system. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#interface xe49 | Enter interface mode. |
(config-if)#switchport | Configure the interface as Layer 2 |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit interface mode. |
(config)#mcec domain configuration | Entering MCEC mode |
(config-mcec-domain)#domain-address 1111.2222.3333 | Domain address for the Mlag domain |
(config-mcec-domain)#intra-domain link xe49 | Intra domain Link between Mlag domains |
(config-mcec-domain)#domain-system-number 2 | Number to identify the node in domain |
(config-mcec-domain)#exit | Exit MCEC mode |
(config-mcec-domain)#commit | Commit the candidate configuration to the running configuration |
Validation
#sh mlag domain details
------------------------------------
Domain Configuration
------------------------------------
Domain System Number : 1
Domain Address : 1111.2222.3333
Domain Priority : 1000
Intra Domain Interface : xe49
Hello RCV State : Current
Hello Periodic Timer State : Fast Periodic
Domain Sync : IN_SYNC
Neigh Domain Sync : IN_SYNC
Domain Adjacency : UP
------------------------------------
MLAG Configuration
------------------------------------
MLAG-1
Mapped Aggregator : po1
Admin Key : 16385
Oper Key : 16385
Physical properties Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Neigh Admin Key : 32769
Neigh Physical Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Info RCV State : Current
Info Periodic Time State : Standby
Mlag Sync : IN_SYNC
Mode : Active-Active
Current Mlag State : Active
MLAG-2
Mapped Aggregator : po2
Admin Key : 16386
Oper Key : 16386
Physical properties Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Neigh Admin Key : 32770
Neigh Physical Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Info RCV State : Current
Info Periodic Time State : Standby
Mlag Sync : IN_SYNC
Mode : Active-Active
Current Mlag State : Active
#sh etherchannel summary
% Aggregator po1 0
% Aggregator Type: Layer2
% Admin Key: 16385 - Oper Key 16385
% Link: xe57 (5057) sync: 1 (Mlag-active-link)
% Link: xe58 (5058) sync: 1 (Mlag-active-link)
% Aggregator po2 0
% Aggregator Type: Layer2
% Admin Key: 16386 - Oper Key 16386
% Link: xe9 (5009) sync : 1 (Mlag-active-link)
% Link: xe10 (5010) sync: 1 (Mlag-active-link)
#sh mlag 1 detail
MLAG-1
Mapped Aggregator : po1
Admin Key : 16385
Oper Key : 16385
Physical properties Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Neigh Admin Key : 32769
Neigh Physical Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Info RCV State : Current
Info Periodic Time State : Standby
Total Bandwidth : 20g
Mlag Sync : IN_SYNC
Mode : Active-Active
Current Mlag State : Active
sh mcec statistics
Unknown MCCPDU received on the system : 0
------------------------------------
IDP xe49
------------------------------------
Valid RX Hello PDUs : 398
Valid TX Hello PDUs : 417
Valid RX Info PDUs : 16
Valid TX Info PDUs : 6
Valid RX Mac Sync PDUs : 3
Valid TX Mac Sync PDUs : 4
MLAG 1
Valid RX Info PDUs : 8
Valid TX Info PDUs : 3
MLAG 2
Valid RX Info PDUs : 8
Valid TX Info PDUs : 3
sh mlag domain summary
------------------------------------
Domain Configuration
------------------------------------
Domain System Number : 1
Domain Address : 1111.2222.3333
Domain Priority : 1000
Intra Domain Interface : xe49
Domain Adjacency : UP
------------------------------------
MLAG Configuration
------------------------------------
MLAG-1
Mapped Aggregator : po1
Physical properties Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Total Bandwidth : 40g
Mlag Sync : IN_SYNC
Mode : Active-Active
Current Mlag State : Active
MLAG-2
Mapped Aggregator : po2
Physical properties Digest : dd 9c f 76 dd b6 5f 2f eb a1 d3 bb 8d 96 fc 82
Total Bandwidth : 40g
Mlag Sync : IN_SYNC
Mode : Active-Active
Current Mlag State : Active
Last modified date: 07/06/2023