flintlock

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

What is flintlock?

🎉 This project was originally developed by Weaveworks but is now owned & run by the community. If you are interested in helping out please reach out.

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

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 #liquidmetal channel on the CNCF slack.

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:

NOTE: we no longer support using the Weaveworks fork (with macvtap) of Firecracker. If you want macvtap then please use Cloud Hypervisor as the vm provider.

NOTE: Cloud Hypervisor before v48.0 does not start on some hosts with newer Intel CPUs, see #1265.

License

MPL-2.0 License

Acknowledgements

The biggest acknowledgement goes to @Weaveworks who where pioneers in the early Kubernetes world and produced some fantastic open source that lives on despite the demise of the company. A big thank you to the company and everyone that worked there. It was the engineers at Weaveworks that originally created Liquid Metal. RIP Weaveworks.