GENEVE traffic performance drops on BCM574XX BCM575XX and BCM576XX NICs in Enhanced data path (EDP) mode

Products

• VMware vSphere ESXi
• VMware Cloud Foundation
• VMware NSX

Issue/Introduction

This article describes a hardware limitation affecting BCM574XX  BCM575XX and BCM576XX NICs when processing GENEVE traffic in EDP mode. An intermittent issue has been identified where GENEVE traffic fails to steer to the designated RXqueue, resulting in packets being incorrectly routed to the default RX queue and potentially degrading performance.

Environment

• VMware Cloud Foundation 9.x
• VMware NSX
• VMware vSphere ESX

Cause

This is caused because of NIC firmware issue.

Resolution

This is a known issue affecting BCM575XX and BCM576XX and Broadcom is aware of it.This issue will be resolved in bnxtnet firmware version 2.37

For BCM574XX, This issue will be resolved in bnxtnet firmware version 2.38

As a temporary workaround, disable and then re-enable the vmnic interface via the command line

• esxcli network nic down -n vmnicX
• esxcli network nic up -n vmnicX