Virtual Machine console display shows black screen for GUI based linux VMs in Cloud director

Products

• VMware Cloud Director

Issue/Introduction

• Console is accessible for Windows and terminal based linux VMs, however not for UI based linux VMs from Cloud director and vCenter. This was tested with CentOS, Ubuntu flavors of Linux and it is possible that this issue might also be noticed on other linux flavors where UI edition is available.
• Console is connected and we could see the cursor change once we click inside the console, however it stays black even on different browsers and systems
• When VM is deployed from VCD, console is not accessible from vCD and vCenter. If VM is deployed from vCenter and imported to vCD, console is accessible at both locations - vCenter and vCD.

Environment

VMware Cloud director 10.x 
vCenter server 8.x
ESXi 8.x

Cause

vCenter server assigns 4 MB of video memory by default when VMs are deployed via APIs or Powershell. This default video memory size is not sufficient for UI based linux VMs.

Resolution

To resolve this issue:

• For existing virtual machine's - Increase video memory to 8MB from vCenter.

1. 1. Shut down the virtual machine.
   2. Right-click on the virtual machine and click Edit Settings.
   3. Expand the Video Card tab and assign video memory.

• To manage video memory for new VM deployments in Cloud director, create a sizing policy.

1. 1. Create VM sizing policy
   2. In 'Special VM Configuration Settings' section, add key 'svga.vramSize' with value in bytes. For ex" '8388608' fo 8 MB.
   3. Add a VM Sizing Policy to an Organization VDC and select the same for new VM deployments.