WARNING: TX hang detected! Reset Uplink

Products

• VMware vSphere ESXi

Issue/Introduction

• Intel X7xx NICs flapping due to TX hang error 
• Virtual machine suffers from a network down event or experiences port flaps
• i40en NIC driver is older than 2.7.2.0
• The following error is found in vmkernel.log under /var/run/log/

[YYYY-MM-DDTHH:MM:SS] cpu##:#######)WARNING: TX hang detected! Reset Uplink 1

Environment

7.x
8.x

Cause

A VM generates packets that are considered malicious by Intel X7xx NICs due to their size being under 64 bytes which will hang the TX queue and cause a network impacting event.

Resolution

This is fixed with Intel driver i40en 2.7.2.0

Finding IO Drivers in the Broadcom Support Portal

NOTE: For customers utilizing the ENS specific version of the drivers, starting with i40en 2.2.x and above the ENS specific functions are no longer a separate driver and are under the unified i40en driver.