NVIDIA MLNX-OS LAG and LACP Configuration Guide

NVIDIA Mellanox switches running MLNX-OS are common in HPC and storage fabrics, and link aggregation is usually the first feature you configure: bonding two or four 25/40/100G ports into one logical port-channel doubles the bandwidth and removes single-link risk. This guide walks through MLNX-OS LAG and LACP configuration from scratch: creating the port-channel, assigning member ports, choosing static vs LACP modes, and verifying the bundle with the right show commands.

Step 1: Create the Port-Channel

switch (config) # interface port-channel 1
switch (config interface port-channel 1) # switchport mode trunk
switch (config interface port-channel 1) # switchport trunk allowed vlan add 10,20,30
switch (config interface port-channel 1) # exit

MLNX-OS uses interface port-channel <id> like IOS. The port-channel inherits switchport settings; here it is a trunk carrying VLANs 10, 20 and 30.

Step 2: Assign Member Ports with LACP

switch (config) # interface ethernet 1/1
switch (config interface ethernet 1/1) # channel-group 1 mode active
switch (config interface ethernet 1/1) # exit
switch (config) # interface ethernet 1/2
switch (config interface ethernet 1/2) # channel-group 1 mode active
switch (config interface ethernet 1/2) # exit

mode active enables active LACP (802.3ad) - the switch actively sends LACPDUs. Use mode passive to wait for the peer, or mode on for a static (non-LACP) bundle when the peer does not support LACP.

Step 3: Save the Configuration

switch (config) # exit
switch # write memory
Success.

Verification Commands

show interfaces port-channel 1
show interfaces port-channel summary
show lacp
show lacp interfaces
show interfaces ethernet 1/1
show interfaces counter port-channel 1

show interfaces port-channel 1 shows the bundle state and member ports; show lacp interfaces displays LACP partner state for each member (look for BNDL/Collecting-Distributing state - if members show AGG but not BNDL, the peer is not matching the LACP config).

Common Issues and Fixes

Port-Channel Load Balancing

switch (config) # port-channel load-balance ethernet dst-ip
switch (config) # port-channel load-balance ethernet l4-src-port

MLNX-OS lets you pick the hash fields for the bundle; for storage/NFS traffic, include L4 ports to spread flows across members.

Best Practices

• Use LACP (mode active) instead of static bundles where possible - it detects mis-wiring and dead links.
• Keep all members on the same speed and VLAN settings.
• For storage fabrics, verify the hash policy spreads traffic or a single member will saturate.

Related: Mellanox switch port types in MLNX-OS and Dell OS10 port-channel and LACP configuration.

原文链接：https://docs.nvidia.com/networking/display/MLNXOSv31120/