Web console cannot be accessible when some VMs turn to Screen Blank after a period of inactivity

Products

• Remote Console
• VMware vSphere ESXi

Issue/Introduction

• Existing web console will turn to black screen and a new Web Console cannot be launched for virtual machine (VM) with Linux based OS
• The login GUI displayed with black screen and with no response via mouse and keyboard it may display "Couldn't establish a connection to the VM web console."
• This happens more likely in latest released Linux OSes, like Ubuntu 24.04, Ubuntu 24.10, RHEL 10.0 and Fedora 41 etc.

Cause

This is seen if the Guest Operating System turn to Blank screen to save power after a period of inactivity

Resolution

Proceed with the below steps

1. Power Cycle the VM to recover

1. 1. In case that the existing Web Console turns to screen black, Click Send Ctrl+Alt+Del on the console
   2. In case a new Web Console cannot be launched successfully, Launch Remote Console of the VM by VMware Remote Console, and Send Ctrl+Alt+Del from VMware Remote Console Drop-down menu
   3. Proceed to Reboot the Virtual machine
      
      
2. Ensure to login to the VM Guest OS immediately and set Screen Blank with Never from the GuestOS PowerSaving setting