ESX/ESXi host unable to enter maintenance mode in a two node cluster

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

You are experiencing these issues with an ESX/ESXi host when entering Maintenance Mode during host remediation through Update Manager:

• Host fails to enter maintenance mode.
• Tasks and Events show the error:
  
  VM xyz cannot be VMotioned.
  

Environment

VMware vCenter Server 5.x
VMware vCenter Server 6.x
VMware vCenter Server 7.x
VMware vCenter Server 8.x

 

Resolution

This issue occurs when high availability (HA) strict admission control is enabled and only one ESXi host becomes available in the HA cluster once the ESX host upgrade begins.

 

There are two ways to configure the HA cluster to allow for the ESXi host to enter maintenance mode:

 

By disabling strict admission control:

1. Right-click the cluster and click Edit Settings.
2. Under Cluster Features, select VMware HA.
3. Under Admission Control, select Disable: Power on VMs that violate availability constraints.
4. Click OK.

By temporarily disabling VMware HA in the cluster settings:

• Right-click the cluster and click Edit Settings.
• Under Cluster Features, select Turn off VMware HA.
• Click OK.

Additional Information