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We will be happy to enable CPU host-passthrough mode on your KVM VPS upon request.
What is CPU Passthrough?
CPU passthrough, also known as host-passthrough mode, allows your VPS to see and use the actual CPU model and features of the physical host server, rather than a generic virtualized CPU model.
Standard Mode (Default)
- Generic CPU model presented
- Better for live migration
- Maximum compatibility
- Limited CPU features
Passthrough Mode
- Real CPU model exposed
- All CPU features available
- Better for some workloads
- Required for nested virtualization
When You Need CPU Passthrough
Nested Virtualization
Running VMs inside your VPS (Docker, KVM, VirtualBox)
Advanced CPU Features
Access to AES-NI, AVX, AVX2, and other CPU extensions
Software Requirements
Apps that check for specific CPU models or features
Development/Testing
Testing software on specific CPU architectures
Common Use Cases
Docker and Containerization
While Docker itself doesn't require CPU passthrough, nested virtualization (running Docker inside a VM) does. If you're running Docker directly on your VPS, passthrough is not needed.
Nested Virtualization
Running VirtualBox, KVM, VMware, or other hypervisors inside your VPS requires CPU passthrough to access hardware virtualization extensions (Intel VT-x or AMD-V).
Cryptography and Security
Applications using hardware-accelerated encryption (AES-NI) benefit from CPU passthrough to access these instructions directly.
How to Request CPU Passthrough
Open a Support Ticket
Specify VPS IP
Explain Use Case (Optional)
Wait for Confirmation
Reboot VPS
Free Service
CPU passthrough is enabled at no additional charge. Simply request it via support ticket.
Verifying CPU Passthrough
Linux
# Check CPU model
cat /proc/cpuinfo | grep "model name"
# Check for virtualization support
egrep -c '(vmx|svm)' /proc/cpuinfo
# If the output is greater than 0, nested virtualization is availableWindows
Open System Information (msinfo32) and check the Processor description. With passthrough enabled, you should see the actual host CPU model.
Limitations and Considerations
Live Migration
VPS cannot be easily live-migrated between different CPU models
CPU Dependencies
VPS becomes dependent on specific CPU features of the host
Performance
Doesn't necessarily mean better performance for all workloads
Not Required for Most Users
Most applications and workloads don't need CPU passthrough. Only request it if you have a specific requirement like nested virtualization or applications that need particular CPU features.
Troubleshooting
Nested Virtualization Still Not Working
- • Ensure you've rebooted your VPS after passthrough was enabled
- • Check that your kernel supports KVM (modprobe kvm-intel or kvm-amd)
- • Verify /dev/kvm exists
- • Check kernel logs for virtualization-related errors
Application Still Can't Find CPU Features
- • Ensure the application is compiled to use the features
- • Check that libraries support the CPU instructions
- • Verify the application isn't checking for bare-metal systems
Need Help?
To request CPU passthrough or if you have questions about whether you need it, open a support ticket. Include your VPS IP address and describe your use case so we can provide the best guidance.