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OpenZFS

A combined volume manager and filesystem with strong integrity guarantees.

OpenZFS is the open-source descendant of Sun Microsystems' ZFS. It pairs a copy-on-write filesystem with a built-in volume manager (zpool), so storage administration happens in a single unified tool rather than the layered LVM-on-top-of-mdadm-on- top-of-disks stack that Linux usually uses. Snapshots, clones, transparent compression, end-to-end checksumming, software RAID with self-healing, and incremental send/receive replication are all first-class features.

ZFS's data integrity guarantees are unusually strong. Every block is checksummed; reads that fail their checksum are automatically repaired from a redundant copy if one exists. This catches and fixes silent data corruption (bit rot, bad RAM, bad cables) that other filesystems would silently return as good data.

ZFS's licence (CDDL) is incompatible with the Linux kernel's GPL-2.0, so on Linux it ships as an out-of-tree module rather than mainlined. FreeBSD, illumos, and several NAS operating systems (TrueNAS, Proxmox, Unraid) ship ZFS natively. Its mature design and strong integrity guarantees make it the default for serious storage workloads where data loss is unacceptable.

Debian:   sudo apt install zfsutils-linux
Ubuntu:   sudo apt install zfsutils-linux   # has been integrated into Ubuntu
Fedora:   see https://openzfs.github.io/openzfs-docs/Getting%20Started/Fedora/
Arch:     install zfs-dkms from AUR