# Ubuntu 16.04 LTS and newer:
$ sudo apt install zfsutils-linux
$ zpool list
$ zpool create hdd /dev/vdb -f -m /mnt/hdd -o ashift=12
$ zpool create ssd /dev/vdc -f -m /mnt/ssd -o ashift=12
$ zpool status
$ zfs set mountpoint=/mnt/hdd hdd
$ zfs set mountpoint=/mnt/ssd ssd
$ zpool history
$ zdb
$ zpool iostat 1
$ zpool scrub hdd && zpool status
$ zfs mount -a
$ zfs get mounted
Principles
- Copy-on-write: never overwrite an existing block.
- The file system is always consistent.
- The file system state advances atomically at checkpoints.
- Cheap snapshots (read-only) and clones (read/write).
- Metadata redundancy and data checksums.
- Selective data compression and deduplication.
- Pooled storage shared among file systems.
- Mirroring and single, double, and triple parity RAIDZ.
- Space management with quotas and reservations.
- Fast remote replication and backups.