OpenZFS

OpenZFS is an open-source project that maintains a cross-platform implementation of ZFS, a robust filesystem and volume manager originally developed by Sun Microsystems. OpenZFS aims to provide a cohesive, portable codebase across operating systems, notably Linux (ZFS on Linux), FreeBSD, and ports to macOS and others. The project coordinates contributions from a global community and distributes a common set of ZFS userland tools.

Core features include data integrity with end-to-end checksums, a copy-on-write transactional model, and scalable storage pools (zpools) built from vdevs. It supports RAID-Z levels and mirrors, provides snapshots and clones, and enables send/receive for replication. Additional capabilities include optional compression and deduplication, native encryption, and resilience tools such as scrubbing and resilvering.

Architecture and operations: ZFS combines the filesystem and volume manager, using dynamic storage pools and transactional semantics to maintain consistency. Snapshots preserve state over time, while sends/receives enable efficient incremental replication. Built-in compression, deduplication options, and encryption with native keys are available as part of the OpenZFS feature set.

History and governance: OpenZFS arose as an open-source continuation of ZFS development to support multiple platforms beyond Oracle’s stewardship. It coordinates cross-platform development, testing, and releases and is widely adopted in Linux distributions as ZFS on Linux and in FreeBSD, with macOS ports maintained by separate projects.

Licensing: OpenZFS code is released under the Common Development and Distribution License (CDDL). Licensing and integration considerations have been part of discussions around incorporating ZFS into various operating systems.