Autonegotiation between switches and ESXi host Fails

Products

• VMware vSphere ESXi

Issue/Introduction

• Autonegotiation from the physical switch point of view to any network device (ESXi Host) is a physical layer function between the switch hardware and the network interface (NIC).
• Fast Link Pulses (FLPs) and similar signaling defined in IEEE 802.3. are used for this function.
• Autonegotiation is a signaling mechanism and procedure used by Ethernet over twisted pair by which two connected devices choose common transmission parameters, such as speed, duplex mode, and flow control. In this process, the connected devices first share their capabilities regarding these parameters and then choose the highest-performance transmission mode they both support.
• It is not a function of the Server (Host) Operating System (OS).
  
• After replacing NIC card their status is Down.  They are configured for autonegotiation.
• The replacement NICs will not come up unless the speed is set statically.
• Autonegotiation is failing.

 

Environment

VMware vSphere
VMware NSX

Cause

• Driver and firmware of the hardware depend on drivers and firmware for autonegotiate to work.
• It must also be configure on the switch.

Resolution

Vmnics Might Be Down After an Upgrade to ESXi 8.0

Configuring the speed and duplex of an ESXi host network adapter