amend heartbeat scenarios

Author: modularity

articles/lab-services/media/troubleshoot-access-lab-vm/lab-vm-alert-hover.png

@@ -12,7 +12,7 @@ ms.date: 12/05/2022
 
 # Troubleshoot accessing lab VMs in Azure Lab Services
 
-In this article, you learn about the different approaches for troubleshooting lab VMs. Understand how each approach affects your lab environment and user data on the lab VM. There can be different reasons why you're unable to connect to a lab VM in Azure Lab Services, or why you're stuck to complete a course. For example, the underlying VM is experiencing issues, your organization's firewall settings have changed, or a software change in the lab VM operating system.
+In this article, you learn about the different approaches for troubleshooting lab VMs. Understand how each approach affects your lab environment and user data on the lab VM. There can be different reasons why you're unable to access to a lab VM in Azure Lab Services, or why you're stuck to complete a course. For example, the underlying VM is experiencing issues, your organization's firewall settings changed, or a software change in the lab VM operating system.
 
 ## Prerequisites
 
@@ -24,25 +24,47 @@ In this article, you learn about the different approaches for troubleshooting la
 
 To use and access a lab VM, you connect to it by using Remote Desktop (RDP) or Secure Shell (SSH). You may experience difficulties to access your lab VM:
 
-- You're unable to connect to the lab VM from your computer by using RDP or SSH. There might be a problem with the underlying VM, or a network or firewall configuration might prevent you from connecting.
+- You're unable to start the lab VM
 
-- You're unable to login to the lab VM.
+- You're unable to connect to the lab VM from your computer by using RDP or SSH 
 
-- After connecting to the lab VM, the VM is not working correctly.
+- You're unable to login to the lab VM
+
+- After connecting to the lab VM, the VM isn't working correctly
 
 ## Troubleshooting steps
 
+### Unable to start lab VM
+When our service is unable to maintain connection with a lab VM, a warning appears next to the lab VM name. 
+
+:::image type="content" source="./media/troubleshoot-access-lab-vm/lab-vm-alert.png" alt-text="Screenshot that shows an alert next the lab VM name.":::
+
+If you see a lab VM alert next to its name, then hover over it to read the error message. This message might state that _"Our cloud virtual machine has become non-responsive and will be stopped automatically to avoid overbilling."_
+
+:::image type="content" source="./media/troubleshoot-access-lab-vm/lab-vm-alert-hover.png" alt-text="Screenshot that shows an alert message when the cursor hovers over an alert next to the lab VM name.":::
+
+Scenarios might include:
+
+|Scenario|Cause|Resolution|
+|-|-|-|
+|Shutdown lab at OS level |Ending a lab VM session through OS level shutdown |Lab users may start the lab VM at any time without affecting lab connectivity |
+|Network configuration |• Installing a firewall that has outbound rule blocking 443 port <br> • Changing DNS setting, custom DNS solution, can't find our DNS endpoint <br> • Changing DHCP settings or IP address in the VM |Learn more about [supported networking scenarios and topologies for advanced networking](./concept-lab-services-supported-networking-scenarios.md) and review [troubleshooting lab VM connection](./troubleshoot-connect-lab-vm.md) |
+|OS disk full |• Limited disk space prevents the lab VM from starting <br> • A nested virtualization template with a full host disk prevents the lab from publishing|Ensure at least 1 GB of space is available on the primary disk |
+|Lab Services Agent |Disabling the Lab Services agent on the lab VM in any form, including: <br> • Changing system files or folders under C:\WindowsAzure <br> • Modifying services by either starting or stopping the Azure agent |• Check if the idle agent service started, which should be set as a 'Manual' startup task for the VM Agent service to start <br> • If the LabServicesIdleAgent service isn't already running, run a Windows startup task to start it <br> • Students should avoid making changes to any files/folders under C:\WindowsAzure |
+
+If you have questions or need help, review the [Advanced troubleshooting](#advanced-troubleshooting) section.
+
 ### Unable to connect to the lab VM with Remote Desktop (RDP) or Secure Shell (SSH)
 
-1. [Redeploy your lab VM](./how-to-reset-and-redeploy-vm.md#redeploy-a-lab-vm) to another infrastructure node, while maintaining the user data. 
+1. [Redeploy your lab VM](./how-to-reset-and-redeploy-vm.md#redeploy-a-lab-vm) to another infrastructure node, while maintaining the user data 
 
     This approach might help resolve issues with the underlying virtual machine. Learn more about [redeploying versus reimaging a lab VM](#redeploy-versus-reimage-a-lab-vm) and how they affect your user data.
 
-1. [Verify your organization's firewall settings for your lab](./how-to-configure-firewall-settings.md) with the educator and IT admin.
+1. [Verify your organization's firewall settings for your lab](./how-to-configure-firewall-settings.md) with the educator and IT admin
 
     A change in the organization's firewall or network settings might prevent your computer to connect to the lab VM.
 
-1. If you still can't connect to the lab VM, [reimage the lab VM](./how-to-reset-and-redeploy-vm.md#reimage-a-lab-vm).
+1. If you still can't connect to the lab VM, [reimage the lab VM](./how-to-reset-and-redeploy-vm.md#reimage-a-lab-vm)
 
     > [!IMPORTANT]
     > Reimaging a lab VM deletes the user data in the VM. Make sure to [store the user data outside the lab VM](#store-user-data-outside-the-lab-vm).
@@ -55,7 +77,7 @@ When you create a new lab from an exported lab VM image, perform the following s
 
 1. After the lab creation finishes, you can [reset the password](./how-to-set-virtual-machine-passwords.md).
 
-### After logging in, the lab VM is not working correctly
+### After logging in, the lab VM isn't working correctly
 
 The lab VM might be malfunctioning as a result of installing a software component, or making a change to the operating system configuration.
 
@@ -70,11 +92,11 @@ The lab VM might be malfunctioning as a result of installing a software componen
 
 Azure Lab Services lets you redeploy or reimage a lab VM. Both operations are similar, and result in the creation of a new virtual machine instance. However, there are fundamental differences that affect the user data on the lab VM.
 
-When you redeploy a lab VM, Azure Lab Services will shut down the VM, move the VM to a new node in within the Azure infrastructure, and then power it back on. You can think of a redeploy operation as a refresh of the underlying VM for your lab. All data that you saved in the [OS disk](/azure/virtual-machines/managed-disks-overview#os-disk) (usually the C: drive on Windows) of the VM will still be available after the redeploy operation. Any data on the [temporary disk](/azure/virtual-machines/managed-disks-overview#temporary-disk) (usually the D: drive on Windows) is lost after a redeploy operation and after a VM shutdown.
+When you redeploy a lab VM, Azure Lab Services will shutdown the VM, move the VM to a new node in within the Azure infrastructure, and then power it back on. You can think of a redeploy operation as a refresh of the underlying VM for your lab. All data that you saved in the [OS disk](/azure/virtual-machines/managed-disks-overview#os-disk) (usually the C: drive on Windows) of the VM will still be available after the redeploy operation. Any data on the [temporary disk](/azure/virtual-machines/managed-disks-overview#temporary-disk) (usually the D: drive on Windows) is lost after a redeploy operation and after a VM shutdown.
 
 Learn more about how to [redeploy a lab VM in the Azure Lab Services website](./how-to-reset-and-redeploy-vm.md#redeploy-a-lab-vm).
 
-When you reimage a lab VM, Azure Lab Services will shut down the VM, delete it, and recreate a new lab VM from the original template VM. You can think of a reimage as a refresh of the entire VM. After you reimage a lab VM, all the data that you saved on the OS disk (usually the C: drive on Windows), and the temporary disk (usually the D: drive on Windows), is lost. To avoid losing data on the VM, [store the user data outside the lab VM](#store-user-data-outside-the-lab-vm).
+When you reimage a lab VM, Azure Lab Services will shutdown the VM, delete it, and recreate a new lab VM from the original template VM. You can think of a reimage as a refresh of the entire VM. After you reimage a lab VM, all the data that you saved on the OS disk (usually the C: drive on Windows), and the temporary disk (usually the D: drive on Windows), is lost. To avoid losing data on the VM, [store the user data outside the lab VM](#store-user-data-outside-the-lab-vm).
 
 Learn more about how to [reimage a lab VM in the Azure Lab Services website](./how-to-reset-and-redeploy-vm.md#reimage-a-lab-vm).