Slow vMotion performance between ESXi Hosts

Products

• VMware vCenter Server

Issue/Introduction

The issue is often directional, affecting traffic from one specific host to another. 
For example, a vMotion from Host A to Host B might complete in seconds, while a vMotion from Host B to Host A takes an excessive amount of time. 

Environment

VMware vSphere ESXi
VMware vCenter Server

Cause

The traffic shaping is configured on the vSwitch of host for the slow vMotion operation, throttling its outgoing vMotion traffic.

Resolution

Disable the traffic shaping on vSwitch:

For Standard vSwitch:

1. Access your vCenter Server.
2. Navigate to the affected ESXi host.
3. Go to the Configure tab.
4. Under Networking, select Virtual switches.
5. Identify the vSwitch that is configured for vMotion traffic.
6. Click on the Edit icon (pencil) for the identified vSwitch.
7. In the vSwitch properties window, navigate to the Traffic Shaping section.
8. Ensure that the Status option for Traffic Shaping is set to Disabled.
9. Click OK to apply the changes.
10. If the issue affects multiple hosts or is bidirectional, repeat these steps for all relevant ESXi hosts in the cluster.
    

For Distributed vSwitch:

1. Access your vCenter Server.
2. Navigate to the Networking.
3. Under Networking, select Virtual switches.
4. Identify the vSwitch that is configured for vMotion traffic.
5. Click on the Edit icon.
6. In the vSwitch properties window, navigate to the Traffic Shaping section.
7. Ensure that the Status option for Traffic Shaping is set to Disabled.
8. Click OK to apply the changes.