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ZFS is an open source file system developed by Oracle Inc. that provides enhanced data integrity, compression and data snapshots.[1] It combines a logical volume manager and a software RAID into the one filesystem.[2] ZFS volumes can span multiple drives, like a traditional LVM setup. ZFS can effectively reduce disk space consumption and enhance performance when compressing data.

The ZFS filesystem supports up to 256 zettabytes and, if enabled, transparently compresses and decompresses data on the fly, reducing disk space usage. ZFS has various different RAID configurations, which can enhance performance through stripping or provide data redundancy through RAID-Z or mirroring. Redundancy ensures that the server remains operational, even when a critical disk fails. While the system remains up and running, the system enters a degraded state. The situation is mitigated by swapping out the disk with a replacement. However, even when a RAID configuration is not used, ZFS is still powerful because its snapshot, compression and data integrity. Although, data loss on a ZFS system is still possible, the filesystem will not become inconsistent due to corrupt or incomplete writes. This means tools like chkdisk.exe are not required.

System Requirements

Running ZFS has a minimal set of system requirements. Moreover, it is possible for pool corruption to occur if these requirements are not met. A general rule of thumb is that for a minimum of 8 GB of RAM is required and that for each terabyte of disk space, there should be approximately 1GB of RAM in addition to the 8GB minimum.

Minimum Recommended Notes
System Memory 8GB 16GB +1 GB for each terabyte of data
Hard Disk or SSD 4GB 16-32GB An SSD/HDD of any size can be used, but you probably want 4GB or more for OS/data storage
Additional SSD Not strictly needed 64 GB Provides a high speed data cache for caching read/writes from ZFS. Not strictly needed

Error Correcting Memory (ECC) is also commonly recommended, but it is not strictly necessary for home or small office environments.


  1. Oracle (2010). "Oracle Solaris ZFS Administration Guide". Oracle Inc. Retrieved 2017-01-04.
  2. kirkland (2016-06-20). "ZFS". Ubuntu Wiki. Retrieved 2017-01-06.