Flintlock - Create and manage the lifecycle of MicroVMs, backed by containerd.

What is flintlock?

Flintlock is a service for creating and managing the lifecycle of microVMs on a host machine. We support Firecracker and Cloud Hypervisor (experimental).

The original use case for flintlock was to create microVMs on a bare-metal host where the microVMs will be used as nodes in a virtualized Kubernetes cluster. It is an essential part of Liquid Metal and can be orchestrated by Cluster API Provider Microvm.

However, its useful for many other use cases where lightweight virtualization is required (e.g. isolated workloads, pipelines).

Features

Using API requests (via gRPC or HTTP):

• Create and delete microVMs
• Manage the lifecycle of microVMs (i.e. start, stop, pause)
• Configure microVM metadata via cloud-init, ignition etc
• Use OCI images for microVM volumes, kernel and initrd
• Expose microVM metrics for collection by Prometheus
• (coming soon) Use CNI to configure the network for the microVMs

Documentation

See our getting started with flintlock tutorial.

Contributing

Contributions are welcome. Please read the CONTRIBUTING.md and our Code Of Conduct.

You can reach out to the maintainers and other contributors using the #liquid-metal slack channel.

Other interesting resources include:

• The issue tracker
• The list of milestones
• Architectural Decision Records (ADR)
• Getting started with flintlock

Getting Help

If you have any questions about, feedback for or problems with flintlock:

• File an issue.

Your feedback is always welcome!

Compatibility

The table below shows you which versions of Firecracker are compatible with Flintlock:

Flintlock	Firecracker	Cloud Hypervisor
v0.5.0	Official v1.0+ or v1.0.0-macvtap	v26.0
v0.4.0	Official v1.0+ or v1.0.0-macvtap	Not Supported
v0.3.0	Official v1.0+ or v1.0.0-macvtap	Not Supported
<= v0.2.0	<= v0.25.2-macvtap	Not Supported
<= v0.1.0-alpha.6	<= v0.25.2-macvtap	Not Supported
v0.1.0-alpha.7	Do not use	Not Supported
v0.1.0-alpha.8	<= v0.25.2-macvtap	Not Supported

Note: Flintlock currently requires a custom build of Firecracker if you plan to use macvtap available here.

License

MPL-2.0 License