ZFS

ZFS is a combined file system and logical volume manager designed by Sun Microsystems. The features of ZFS include protection against data corruption, support for high storage capacities, efficient data compression, integration of the concepts of filesystem and volume management, snapshots and copy-on-write clones, continuous integrity checking and automatic repair, RAID-Z and native NFSv4 ACLs.

ZFS was originally implemented as open-source software, licensed under the Common Development and Distribution License (CDDL). The ZFS name is registered as a trademark of Oracle Corporation.

OpenZFS is an umbrella project aimed at bringing together individuals and companies that use the ZFS file system and work on its improvements.

Features

Data integrity

One major feature that distinguishes ZFS from other file systems is that ZFS is designed with a focus on data integrity. That is, it is designed to protect the user's data on disk against silent data corruption caused by data degradation, current spikes, bugs in disk firmware, phantom writes (the previous write did not make it to disk), misdirected reads/writes (the disk accesses the wrong block), DMA parity errors between the array and server memory or from the driver (since the checksum validates data inside the array), driver errors (data winds up in the wrong buffer inside the kernel), accidental overwrites (such as swapping to a live file system), etc.

ZFS (disambiguation)

ZFS may refer to:

ZFS+

ZFS+ is a combined file system and logical volume manager software subsystem initially released under Common Development and Distribution License or CDDL license from Sun Microsystems with proprietary data deduplication features added by GreenBytes and subsequently made proprietary for a storage systems product. GreenBytes owns the trademark on ZFS+, not to be confused with Sun Microsystems ZFS trademark.

It appears that ZFS+ has now been rebranded as GBFS (GreenBytes File System)

Products

GreenBytes created a storage appliance, called Cypress NAS Filer, originally based upon the Sun Microsystems x86-64-based Sun Fire X4500 platform, and bundled their ZFS+ implementation as a value-add technology. GreenBytes claims their ZFS+ technology can reduce storage power consumption by 50%.

References