Unable to start VM - Agent status Not Ready

Question

No changes were made on VM whatsoever, and today its not starting.

Agent status: Not Ready

Status: Stopped

gives error

1. File: \Windows\System32\winload.efi
2. Error code: 0xc0430001

Answer 1

If your Azure VM is showing an agent status of "Not Ready" and is not starting despite the portal indicating that it was started successfully, you can follow these troubleshooting steps:

1. Check the VM Status: Ensure that the VM is indeed running. You can verify this in the Azure portal by navigating to the Virtual machines section and checking the status.
2. Restart the Guest Agent: If the agent status is "Not Ready", it may be necessary to restart the Azure VM Guest Agent. For Windows VMs, you can do this by connecting via Remote Desktop Protocol (RDP) and restarting the service. For Linux VMs, connect via SSH and restart the service named waagent or walinuxagent.
3. Check Connectivity: Ensure that the VM can connect to the Azure Fabric Controller. You can test this by using a tool like curl to check connectivity to the IP address 168.63.129.16 on ports 80, 443, and 32526. If there are connectivity issues, check your firewall settings.
4. Review Logs: Check the logs located in /var/log/waagent.log for Linux VMs or WaAppAgent.log for Windows VMs. Look for any error messages that might indicate why the agent is not ready.
5. Verify Auto-Update Settings: Ensure that auto-update is enabled for the Azure Linux Agent by checking the configuration in /etc/waagent.conf. The setting should be AutoUpdate.Enabled=y.
6. Check for Extensions Issues: If the agent status is "Not Ready" or blank, it might indicate that the Guest Agent isn't installed or isn't functioning properly. Ensure that all VM extensions are in a "provisioning succeeded" state.

By following these steps, you should be able to diagnose and potentially resolve the issue with the VM agent status and startup problems.

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References:

• Troubleshoot Azure Windows VM Agent issues
• Troubleshoot the Azure Linux Agent

Answer 2

Hello Dov Pru

For this issue Azure virtual machine failed to start without any recent configuration or infrastructure changes.

• Boot Error:
  • File: \Windows\System32\winload.efi
  • Error Code: 0xc0430001

The VM was not able to complete the boot process.

Root Cause:

The issue was caused by a Windows Update–related boot corruption, impacting the Windows boot loader (winload.efi). Recovery attempts were blocked due to BitLocker encryption on the OS disk.

Troubleshooting Steps Performed:

1. Created a snapshot of the affected VM.
2. Extracted the VHD from the snapshot and attempted to create a new VM using the same disk.
   • Result: The newly created VM also failed to boot.
3. Attempted to use the Repair VM option by attaching the OS disk to a recovery VM for troubleshooting.
   • Limitation: The OS disk was BitLocker encrypted, which prevented us from proceeding with further repair and troubleshooting steps.
4. As no successful repair was possible and the disk could not be accessed due to encryption, Dov proceeded with a restore operation.

Resolution:

• The VM was restored successfully from the August backup, which was the latest available healthy recovery point.

Recommendation:

Ensure Azure VM backups are taken regularly and kept up to date. Relying on older restore points can result in data loss, as only the data available at the time of the last successful backup can be recovered. Regular backups help minimize data loss and improve recovery outcomes in similar scenarios