nmlx5 Driver generates numerous L2TableIndex modified Events in ESXi

Products

• VMware vSphere ESXi

Issue/Introduction

Observing frequent nmlx5_en_L2TableIndexAdd/Remove events generated by the Mellanox nmlx5 driver in the ESXi VMkernel log.

yyyy-mm-ddThh:mm:ss cpu143:2097772)<NMLX_INF> nmlx5_core: vmnic5: nmlx5_en_L2TableIndexRemove - (nmlx5_core_en_main.c:7744) Delete 0:xx:xx:xx:xx:xx from L2 table
yyyy-mm-ddThh:mm:ss cpu143:2097772)<NMLX_INF> nmlx5_core: vmnic5: nmlx5_en_L2TableIndexAdd - (nmlx5_core_en_main.c:7631) Add 0:xx:xx:xx:x:x to L2 table
yyyy-mm-ddThh:mm:ss cpu96:2097772)<NMLX_INF> nmlx5_core: vmnic1: nmlx5_en_L2TableIndexRemove - (nmlx5_core_en_main.c:7744) Delete 0:xx:xx:xx:xx:xx from L2 table
yyyy-mm-ddThh:mm:ss cpu96:2097772)<NMLX_INF> nmlx5_core: vmnic1: nmlx5_en_L2TableIndexAdd - (nmlx5_core_en_main.c:7631) Add 0:xx:xx:xx:xx:xx to L2 table

Environment

VMware vSphere ESXi 7.x
VMware vSphere ESXi 8.x

Cause

This is an expected behavior. Each time the VMkernel's NetQ load balancer attempts to add a MAC filter associated with a vmnic queue, the event nmlx5_en_L2TableIndexAdd is recorded in the ESXi log.

Conversely, when a filter is removed from the queue, the event nmlx5_en_L2TableIndexRemove is logged.

These events are also triggered when the movement of filters is influenced by the total number of MAC filters (including those for virtual machines and VM kernels) present on the host, as well as the load on a specific receive (Rx) queue, which is managed by the Load Balancer.

Resolution

These events provide updates regarding changes in traffic filtering within the L2 table.

They are purely informational and do not have any functional impact on the system's performance.

Additional Information

Dell Mellanox: nmlx5 Driver generates numerous L2TableIndex modified Events in ESXi. | Dell India