• When performing a vMotion migration, this compatibility warning is displayed:
  
  Migration from source_server: No guest OS heartbeats are being received. Either the guest OS is not responding or VMware tools is not configured properly .
• In the vpxd.log file, you see entries similar to:
  
  vpxd-2223.log(49294): guestHeartbeatStatus = "gray",
  vpxd-2223.log(50975): [2012-01-09 09:40:44.194 02468 trivia 'VmCheck' opID=3599E879-00000134-82] >>> Invoking VmTestFunctions::GuestHeartbeat
  vpxd-2223.log(50976): [2012-01-09 09:40:44.194 02468 trivia 'VmCheck' opID=3599E879-00000134-82] [4+] GuestHeartbeat
  vpxd-2223.log(50977): [2012-01-09 09:40:44.194 02468 verbose 'VmCheck' opID=3599E879-00000134-82] VmTestFunctions::GuestHeartbeat 1 warnings reported
  error = (vmodl.MethodFault) null,
  result = (vim.vm.check.Result) [
  (vim.vm.check.Result) {
  dynamicType = <unset>,
  vm = 'vim.VirtualMachine:vm-301',
  host = 'vim.HostSystem:host-23',
  warning = (vmodl.MethodFault) [
  (vim.fault.NoGuestHeartbeat) {
  dynamicType = <unset>,
  faultCause = (vmodl.MethodFault) null,
  msg = "No guest OS heartbeats are being received. Either the guest OS is not responding or VMware Tools is not configured correctly.",

To workaround the warning, perform one of these options:

• Ensure that the VMware Tools are installed in the virtual machine before performing a migration.
• Ensure that the virtual machine has been running long enough for the operating system to be completely started before performing a migration.
• Restart the VMware Tools service.

For Windows virtual machine:

1. Click Start > Run, type services.msc, and press OK.
2. Right-click VMware Tools Service and click Restart.

For Linux virtual machine, run the command:

Linux machines using init.d: /etc/init.d/vmware-tools restart
     
Linux machines using systemd: /etc/vmware-tools/services.sh restart

If your issue continues to exist, reinstall VMware Tools to ensure that you are on the latest version.