EuroBSDCon 2025

Bring Cloud-Native Networking to FreeBSD Jails: Porting Calico from Linux
2025-09-27 , D1

While Linux containers benefit from a rich ecosystem of Container Network Interface (CNI) plugins such as Calico and Cilium, FreeBSD Jails have lacked native, standardized solutions for advanced networking. As a result, users have relied on manual, error-prone configurations, which limit scalability and integration with modern orchestration platforms.
This presentation introduces porting Calico, a widely adopted CNI plugin, to the FreeBSD operating system. Our approach replaced Linux-specific components with FreeBSD-native equivalents: iptables with ipfw, netlink sockets with routing sockets, and Linux network namespaces with FreeBSD’s vnet.
This work aims to bridge the gap between Linux and BSD container networking. By providing scalable, policy-driven capabilities that are compatible with existing Linux-centric infrastructure, FreeBSD will be empowered to participate more fully in the broader container networking ecosystem.

Souma Sakaguchi is a graduate student at Future University Hakodate, Japan. His research focuses on container networking, virtualization, and operating system compatibility between Linux and FreeBSD. Currently, he is exploring Linux-compatible container networking for FreeBSD.