ESXI-06-100042 - The VMM must automatically terminate a user session after inactivity timeouts have expired or at shutdown by setting an idle timeout on shell services.
When the ESXi Shell or SSH services are enabled on a host they will run indefinitely. To avoid having these services left running set the ESXiShellTimeOut. The ESXiShellTimeOut defines a window of time after which the ESXi Shell and SSH services will automatically be terminated.
From the vSphere Client select the ESXi Host and go to Configuration >> Advanced Settings. Select the UserVars.ESXiShellTimeOut value and configure it to 600. or From a PowerCLI command prompt while connected to the ESXi host run the following commands: Get-VMHost | Get-AdvancedSetting -Name UserVars.ESXiShellTimeOut | Set-AdvancedSetting -Value 600