How to Identify and Fix a Hypervisor Error

Did you know a single misstep in your hypervisor settings can cause crashes that feel impossible to fix? Let’s make sure that doesn’t happen to you.

This guide will teach you everything you need to know to identify and fix hypervisor errors. It explains what a hypervisor is and tackles common issues like BSOD, driver conflicts, and memory problems. You'll also learn simple troubleshooting steps, how to configure your system correctly, and best practices for setting up virtual machines. The guide also covers crash recovery, diagnostic tools, and advanced tips for optimizing virtualization.

So, without further ado, let’s begin.

Table of Contents

• Understanding Hypervisor Errors
  • What is a Hypervisor?
  • Common Hypervisor Errors and Their Causes
• Troubleshooting Techniques
  • Fixing BSOD Related to Hypervisors
  • Resolving Driver Conflicts in Virtualization
  • Diagnosing Hypervisor-Related Memory Issues
• System Updates and Configuration
  • Proper Configuration of BIOS Settings
  • How to Update Drivers for Hypervisor Stability
  • Best Practices for Virtual Machine Configuration
• Recovery and Error Resolution
  • Recovering from Hypervisor-Related Crashes
  • Using Diagnostic Tools to Identify Issues
  • Steps to Restart and Fix Virtualization Problems
• Advanced Topics
  • Understanding Kernel Panics in Virtualization
  • Compatibility Considerations for Hardware and Hypervisors
  • Optimizing Performance in Hyper-V and Virtualization
• Summary

1. Understanding Hypervisor Errors

Hypervisor errors can be bothersome, so you would like to avoid them always. However, before you can prevent them, you must have a good grasp of what they are.

Let’s begin by defining a hypervisor. 

What is a Hypervisor?

A hypervisor is a software running multiple virtual machines (VMs) simultaneously on a single physical machine. Since the virtual machines share the same host machine, a hypervisor error in the host machine makes all VMs it hosts vulnerable to errors.

Common Hypervisor Errors and Their Causes

Here are some of the common hypervisor errors.

• Stop Errors or Blue Screen of Death (BSOD): BSOD occurs when a critical system in the Windows operating system prevents it from running and secures your computer from further damage. An error message pops up to signify a problem in the hypervisor causing the system malfunction. The most apparent indicator that your system is about to crash is the blue screen with the white text. Besides this, observe if the speed of your computer has decreased, if there are error messages, e.g., HYPERVISOR_ERROR, or if your computer starts to reboot by itself.
• Several factors may cause BSOD:  hardware failures, (e.g., hard drive issues), corrupted drivers, infection from malicious software, overheating, and power supply problems.

• Live migration problem: Live migration happens when a VM is moved from one host machine to another with no disruption to the VM. Problems in live migration may occur because of configuration errors within the hypervisor settings, hardware incompatibility on the receiving or destination host, insufficient resources, and network issues.
• Invalid login: This happens when a password is changed in the hypervisor but not in the system.
• No Hypervisor Found error: This usually happens when the hypervisor is disabled in the Basic Input/Output System (BIOS).

2. Troubleshooting Techniques

Identifying hypervisor errors and knowing their causes won’t be enough to protect your system. Know how to troubleshoot these errors so as not to compromise the VMs.

Below are a few techniques for correcting hypervisor issues.

a. Fixing BSOD Related to Hypervisors

Below is a step-by-step guide for hypervisor-related BSOD.

• STEP 1: Enable virtualization in the BIOS/UEFI settings. Restart your system then press the appropriate key (F2, Delete, or Esc key, depending on your computer) when booting. Scan the Advanced or CPU Configuration section for the option related to Intel VT-x or AMD-V, then enable it.
• STEP 2: Download the newest motherboard and CPU drivers. Do the same for your network adapters, processors, and storage controllers to prevent compatibility issues.
• STEP 3: Check for corrupted system files and repair them. Open the Command Prompt, then type in sfc/scannow. Once scanning is done, type in DISM/Online/Cleanup-Image/RestoreHealth.
• STEP 4: Disable Third-Party Software. Your third-party antivirus or firewall software may conflict with hypervisors. Temporarily disable them to check if they are causing the error.
• STEP 5: Reinstall or Repair the Hypervisor. For Hyper-V: Go to the Control Panel, select Programs, then turn Windows features on or off. Untag Hyper-V, restart, re-tag Hyper-V. For VMware: Try to reinstall the hypervisor software.
• STEP 6: Check for Error Logs and Assess Dump Files. Using Event Viewer, check for hypervisor-related error logs, focusing on those that happened around the time of the BSOD. Use WinDbg to pinpoint which system component caused the error.

b. Resolving Driver Conflicts in Virtualization

Before resolving driver conflicts, recognize the indicators that such a problem exists. Driver conflicts can be manifested in several ways, such as cryptic error messages, erratic device behavior, frequent and unexpected system crashes, malfunctioning computer peripherals, and slow computer performance.

Next, identify the source of the issue. Knowing what’s causing the driver conflict is crucial so you can apply the appropriate solution. Any of the following may cause driver conflicts:

• Hardware changes and upgrades. The existing drivers in your system may not be fit to handle a new hardware component, e.g., a peripheral device, that you install in your system.
• OS and Windows updates. Shifting to a different version of your OS or updating Windows may affect your system, causing the incompatibility of drivers.
• Outdated drivers. Using drivers that are not up-to-date prevents you from fixing system bugs, leads to sluggish system performance, and results in incompatibility with your software and hardware.
• Software changes. Some software applications work only with specific driver configurations. Installing a new software that does not match your current setup, leads to driver conflict issues.

Here’s how to troubleshoot driver conflicts. 

• STEP 1: Pinpoint the problematic driver/s. Perform device manager checks, event log analysis, and system diagnostics to check for any indicators leading to the problematic driver.
• STEP 2: Adapt your driver to the fit version. Updating your driver to the latest version may not be the best solution. Sometimes, the updates done to the driver may be causing the conflict; in which case, you have to revert to the last known working version.
• STEP 3: Uninstall then reinstall drivers. If step 2 doesn’t resolve the conflict, uninstall the identified problematic driver, then reinstall it to eliminate the corrupted files.
• STEP 4: Temporarily disable conflicting drivers. In case of conflicting drivers, temporarily disable them and identify the root cause. This should allow you to arrive at a more appropriate solution.
• STEP 5: Revert your system to a previously known working state. In a worst-case scenario, the “system restore” or “system recovery” options are useful for addressing complicated driver issues.
• STEP 6: Ask an expert for advice. Sometimes, you just have to accept that the problem is beyond your skills. Seek the help of an IT expert.

c. Diagnosing Hypervisor-Related Memory Issues

If you are a Hyper-V user, you can diagnose memory issues using its various memory counters.

• MemoryAvailable Mbytes monitors memory utilization. A count that is under 10% of free RAM warns you of a potential issue. If your free RAM is under 100 MB, you’re in a critical situation and must act immediately.
• MemoryCommitted Bytes checks the VMs’ memory use to determine the amount of memory that must be allocated to each VM.
• The \Hyper-V Dynamic Memory Balancer\Average Pressure counter monitors dynamic memory. The counter must read below 80% if you want your VM to have a robust dynamic memory.

3. System Updates and Configuration

System updates refer to software updates, such as drivers and security updates or version upgrades. On the other hand, system configuration deals with how system updates are applied.

a. Proper Configuration of BIOS Settings

BIOS is a software rooted in hardware that allows you access to your system. It is an essential computer component that triggers off hardware checks, initializes system components, and loads the OS during start-up.

Do the following to configure BIOS:

• Press the F2 key to get into the BIOS Setup utility while the power-on self-test (POST) Is ongoing.
• When the main BIOS Setup menu screen displays, use the arrow and Tab keys to navigate the computer and highlight the fields that need modification.
• Press Enter to display the dialog box with the available options, then select the field.
• Modify the selected Setup field, then shut off the screen. Repeat steps 1 to 4 if other setup parameters need to be modified, then proceed to the next step.
• Press the right arrow key, release it, and wait for the Exit menu to display.
• Save the changes you made before exiting the setup utility.

b. How to Update Drivers for Hypervisor Stability

Updating drivers on a Hyper-V cluster must be done as specified below; otherwise, you might corrupt the virtual switches in Hyper-V.

• Go to Failover Cluster Manager, then pause and drain one node of the cluster, ensuring that clustered nodes can successfully migrate to another node.
• Open Hyper-V Manager on the paused node, then go to Virtual Switch Manager.
• Note which external virtual switch and host network adapter are bound to each other.
• Unbind all virtual switches from the host’s network adapters by re-classifying them as “Private”.
• Update all the required drivers and firmware.
• Return to Virtual Switch Manager in the Hyper-V Manager.
• Re-bind each external switch to their host network adapter.
• Resume the paused node. Repeat the steps for the remaining nodes.

4. Best Practices for Virtual Machine Configuration

The performance of VMs can only be maximized when they are properly configured. Consider the VMs’ memory, processor, security features, and storage.

a. Memory

Proper VM configuration guarantees sufficient Random Access Memory (RAM) that supports the applications and workloads in your system, and adequate virtual memory to support the RAM. Consider the following to ensure your system will have adequate memory to serve your needs.

• Type of available RAM: Use DDR4 RAM because normally, it is more efficient and faster than DD3 RAM
• Amount of available RAM: More RAM means you can multitask and use more complex applications. Know the applications and workloads to run on your VM.
• Available virtual memory size: Should be enough to serve as backup memory in case RAM reaches its maximum capacity
• Type of OS used: Typically, macOS requires less RAM than Linux and Windows.
• Virtualization technology: Hyper-V and VMware require more RAM than other virtualization technologies.

b. Processor

The VMs’ processor must be configured to avoid having applications and workloads reduce the system’s speed. Look into the following factors:

• Optimum virtual cores and threads: Generally, the more cores and threads there are, the better the VM’s performance gets. However, they should not be excessive to avoid wasting resources and system performance issues.
• Type of processors: AMD processors are less powerful than Intel processors.
• Processors’ architecture: CISC aids in efficient memory use and multitasking. X86 Intel is compatible with most software and various OS. RISC is known for energy efficiency

c. Security Feature

A well-configured VM deals with security issues effectively to safeguard the system from external threats. You may adopt the following best practices for security:

• Run the latest antivirus and anti-malware software to protect your system against cyber threats. 
• Run the latest version of the OS and all software running on it to avoid vulnerabilities.
• Use a virtual firewall to prevent and watch out for malicious traffic.
• Turn on two-factor notification for all accounts accessible through the VMs.
• Enable VM isolation to keep VMs separate from one another.
• Be alert — observe any unusual activity in your system.

d. Storage

A properly configured VM prevents sluggish disk access from lowering VM performance. Consider the following to achieve peak performance.

• Type of Storage: Solid State Drives (SSDs) are typically more efficient and reliable than Hard Disk Drives (HDDs).
• Storage availability: The bigger your storage, the better, especially when working with large file types.
• Type of File System: New Technology File System (NTFS) works best with Windows, ext4 with Linux.
• Applications and Workloads: Databases and file servers need more storage space than email servers or web servers.
• Storage technology: Although more expensive, the storage technology (Redundant Array of Independent Disks) RAID and Storage Area Network (SAN) offer better performance and reliability than that of Network Attached Storage (NAS).

5. Recovery and Error Resolution

A hypervisor error may cause your system performance to lag, but you can always recover from these errors.

a. Recovering from Hypervisor-Related Crashes

VMware suggests the following recovery techniques.

• Back up your hypervisor to make it easier to recover from a crash.
• Use a snapshot or a cloned template if you want to recover your hypervisor VM.
• Reinstall a new ESXi host on a USB flash drive or SD card if the hypervisor issue resulted from corrupted boot records or partition table adjustments.

b. Using Diagnostic Tools to Identify Issues

Below are some diagnostic tools to help you identify hypervisor issues.

• Event Viewer: This built-in Window tool finds errors related to Hyper-V.
• Guarded Fabric Diagnostic Tool: Useful for Windows Server 2022, 2019, and 2016, this tool guides administrators in fixing outages and pinpointing improperly configured system assets.
• VMware Skyline Health Diagnostics Tool: A self-service diagnostics tool, it aids in detecting issues affecting the vSphere and vSAN product line. It also recommends corrective actions for the identified issues.

c. Steps to Restart and Fix Virtualization Problems

Restarting virtualization issues may be caused by VM configuration, storage host issues, etc. How to fix them? Follow these steps:

• Check for error messages related to the restart problem in the host operating system’s and virtualization software’s logs.
• Ensure that the VM is properly configured.
• Identify potential resource constrictions by checking CPU and memory usage and the host machine’s disk space.
• Inspect your VM’s integrity by ensuring that its hard disk is accessible and uncorrupted.
• Try to restart your VM on the host system.
• Update virtualization software when necessary.
• Check your VM’s network configuration.

d. Specific virtualization platforms and troubleshooting

Two virtualization platforms dominate the market — VMware and Hyper-V. How do you troubleshoot when something goes wrong with them?

• VMware: Check for issues with the vCenter server, virtual machine snapshots, and resource pools.
• Hyper-V: Review the Hyper-V Manager logs for errors, and check if the virtual machine management service is running correctly.

6. Summary

Hypervisor errors can be frustrating, but you’ve got this. How to start? Start by checking your BIOS settings and tweaking your VM performance. Each small fix helps keep your system steady and reliable. Also, stay ahead of issues by keeping your software updated, monitoring your system’s health, and following smart practices.

You’ve got the knowledge—now it’s time to take action.

Have questions or tips of your own? Share them and let’s keep learning together!