Troubleshoot Session Host Availability

A session host VM may display a status of Unavailable.

Alternatively, an "AVD session host not found" message is displayed:

The status reported here is based on what Nerdio Manager receives from Microsoft's AVD Broker/Management Service, which in turn generates the status based on reports from the AVD Agents installed on the session host VMs. Please see this Microsoft article for current statuses.

The statuses are defined as follows:

• Available: The AVD agent is successfully communicating with the AVD Management Service, and is ready to accept user sessions.

• Unavailable: The AVD agent has not successfully communicated with the AVD Management Service, or the agent is unable to update itself to the latest version. This can also show temporarily while AVD waits for the OS to boot up and the agent to come online. In this scenario, the AVD agent did register to the AVD service.

• AVD Session Host not found: Nerdio Manager has recognized that a VM in Azure was created and linked with Nerdio Manager, but the corresponding agent was either not installed/registered, or has been removed from AVD's registration list. The AVD agent did not register to the AVD service.

All session host VMs must have the AVD agent in order to communicate with the AVD Broker service and receive user sessions. The AVD agent's core components can be found under Remote Desktop Agent Boot Loader and Remote Desktop Services Infrastructure Agent in Programs and Features.

Unless the agent is installed, registered to AVD Service, and able to report its status, the session host VM is unable to receive sessions from the AVD management service.

Because of this, Nerdio Manager does not allow management of a session host VM without the AVD agent installed and registered, since it usually indicates the session host VM was not successfully created, or there is a significant problem with session host VM provisioning. Nerdio Manager does this to prevent you from using the session host VM. An admin should either perform a "clean up" or "resume" on the session host VM creation task before continuing with management of the session host VM.

Optionally, if the session host states "AVD Session host Unavailable," you could attempt to fix the session host VM manually, but this is not recommended because it is more labor intensive.

To fix the problem manually:

1. In the Azure portal, navigate to Azure Virtual Desktop > Host pools.

2. Select the host pool where the session host VM is located.

3. Copy the registration key:

   • Go to the Registration key tab, and then in the right-hand pane that opens, at the bottom of the key box, select Copy.

   • If the key has not been generated yet, generate the new key. For details, see Generate a registration key.

     

4. RDP to the VM that you need to register as a session host and sign in as a local or domain admin.

   Note: When signing in as a local admin, you need to exclude the local admin user from the FSLogix profile.

   To add a user or user group to the FSLogix exclude group with a command:

   1. In the Azure portal, go to Virtual machine > Run command.

   2. Run the command below:

      net localgroup "FSLogix Profile Exclude List" /add /domain\name

      

5. Download and run the AVD agent installer and boot loader for your session host VM as described in this Microsoft article: Step 4: Reinstall the agent and boot loader.

   Important! After manually installing the AVD agent, ensure you reboot the VM, as required in the Microsoft reference above.

   Once you complete the required steps, you should see the session host registered in the host pool with the status Available.