All VMs on an individual host are unable to migrate, create snapshots, etc. Options are grayed out.

Products

• VMware vSAN
• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

• The option to take snapshots and vMotion is grayed out for all VMs on one host in the cluster. 
• The host is connected to the VC and not in a non-responsive or disconnected state. 
• VM consoles for the VMs do not connect.

Environment

VMware vSAN (All Versions)
VMware vCenter (All Versions)
VMware vSphere ESXi (All Versions)

Cause

The host is in a semi-hung state.  The vSAN shows no issues and the host is unresponsive to esxcli command.  Esxcli commands would not return to the command prompt and never posted a timeout or other error message.

Resolution

Steps to resolve

• Restart the hostd and vpxa services on the ESXi host.  /etc/init.d/hostd restart; /etc/init.d/vpxa restart
  • Restarting Management Agents
• If that does not work, reboot the host. 

In some instances it may not be possible to put the host into maintenance mode.  As such the VMs will need to be gracefully shutdown and the host can then be cold booted.  The reboot can allow the host to execute the VM-related functions like vMotion and taking snapshots.  It's unclear if any real vSAN issue was active in the cluster, but rather the ESXi host was in a semi-hung state.