Unavailable Session Host After Deployment

[StephanF135]

Hi everyone,

I've been experimenting with Azure Virtual Desktop and have followed the step-by-step guide here:

https://learn.microsoft.com/en-gb/azure/virtual-desktop/deploy-azure-virtual-desktop 

At first, the deployment worked perfectly: following this guide resulted in a working Windows 11 VM. Trouble was, I could only connect to it using the local admin credentials, not using my Azure AD details - I'm using a non-domain joined device and have followed the instructions to add the various options to the RDP Properties.

So, I thought maybe I'd made a mistake in following the instructions in setting up the , or Host Pool. So, I removed everything, deleted the VM and cleared it down (except the network).

I re-created everything as per the instructions and now, any time I create a new session host, it deploys successfully but remains "unavailable" in the host pool:

I can connect to it via the serial console under VMs and can show it's running. 

Things I have already tried:

• Restarting the RDAgentBootLoader service (per this article) via the serial console
• Restarted the VM
• Waited several hours in case it came back
• Deleted the VM and created a new session host with a different Windows build

The VM appears to be running perfectly, but the connection between the VM and the Host Pool seems to be broken. The VM is in EntraID rather than Active Directory, if it makes any difference.

Any suggestions are very welcome. I've probably done something daft.

[#2]

@StephanF135 login to the vm as local admin and check the event logs. There should be something indicating why.

[#3]

If you're encountering an "Unavailable Session Host After Deployment" issue, it could indicate a variety of potential problems. Common causes may include network configuration issues, insufficient resources on the host machine, or errors during the deployment process. To resolve this, check your network settings, ensure that the host machine meets the necessary requirements, and review deployment logs for any errors. Additionally, consider reaching out to technical support or consulting relevant documentation for further assistance tailored to your specific deployment environment.

[#4]

@StephanF135 

Would suggest to retrieve logs to tell you the story

[#5]

Open Event Viewer and go to Windows and check Application logs.

[#6]

Open Event Viewer and go to Windows and check Application logs.

[#7]

• Solution 1: Check the domain join of session host if not join it manually
• Solution 2: Verify URL Accessibility

• Access the Session Host via RDP:

• Take the Remote Desktop Protocol (RDP) connection to the created session host.

• Check URL Accessibility:

• Open Command Prompt (CMD) with administrator privileges.
• Navigate to the directory: C:\Program Files\Microsoft RDInfra\RDAgent_1.0.8431.2300.
• Run the command: .\WVDAgentUrlTool.exe.

• Verify Endpoint Access:

• Follow the guidelines provided by Microsoft: Check access to required FQDNs and endpoints for Azure Virtual Desktop.
• If the URL is not accessible, ensure it is allowed through your network or firewall settings.

• Solution 3: Re-register the Session Host in the Host Pool

• Access the Session Host via RDP:

• Take the RDP of the created session host or the problematic server with administrative privileges.

• Download Necessary Agents:

• Download the required agents from the following links:

• Azure Virtual Desktop Agent
• Azure Virtual Desktop Agent Bootloader

• Unblock Downloaded Files:

• For each downloaded file (agent and bootloader), unblock them:

• Right-click on the file, select Properties, click Unblock, and then select OK.

• Generate a New Registration Key:

• Sign in to the Azure portal.
• Search for "Azure Virtual Desktop" and select the corresponding service.
• Navigate to Host pools and select the name of the host pool containing your session host VM.
• In the Overview blade, select Registration key to generate a new key.

• Install the Bootloader:

• Run the bootloader installer on the session host.

• Restart the Session Host VM:

• Restart the virtual machine to complete the re-registration process.

• By following these steps, you should be able to resolve the common issues associated with Azure Virtual Desktop session hosts. If problems persist, further investigation into network configurations or additional Azure support may be required.