ZFS-SNAPSHOT(8) FreeBSD System Manager's Manual ZFS-SNAPSHOT(8)
NAME
zfs-snapshot - create snapshots of ZFS datasets
SYNOPSIS
zfs snapshot [-r] [-o property=value]<?> dataset@snapname<?>
DESCRIPTION
Creates a snapshot of a dataset or multiple snapshots of different
datasets.
Snapshots are created atomically. That is, a snapshot is a consistent
image of a dataset at a specific point in time; it includes all
modifications to the dataset made by system calls that have successfully
completed before that point in time. Recursive snapshots created through
the -r option are all created at the same time.
zfs snap can be used as an alias for zfs snapshot.
See the Snapshots section of zfsconcepts(7) for details.
-o property=value
Set the specified property; see zfs create for details.
-r Recursively create snapshots of all descendent datasets
EXAMPLES
Example 1: Creating a ZFS Snapshot
The following command creates a snapshot named yesterday. This snapshot
is mounted on demand in the .zfs/snapshot directory at the root of the
pool/home/bob file system.
# zfs snapshot pool/home/bob@yesterday
Example 2: Creating and Destroying Multiple Snapshots
The following command creates snapshots named yesterday of pool/home and
all of its descendent file systems. Each snapshot is mounted on demand
in the .zfs/snapshot directory at the root of its file system. The
second command destroys the newly created snapshots.
# zfs snapshot -r pool/home@yesterday
# zfs destroy -r pool/home@yesterday
Example 3: Promoting a ZFS Clone
The following commands illustrate how to test out changes to a file
system, and then replace the original file system with the changed one,
using clones, clone promotion, and renaming:
# zfs create pool/project/production
populate /pool/project/production with data
# zfs snapshot pool/project/production@today
# zfs clone pool/project/production@today pool/project/beta
make changes to /pool/project/beta and test them
# zfs promote pool/project/beta
# zfs rename pool/project/production pool/project/legacy
# zfs rename pool/project/beta pool/project/production
once the legacy version is no longer needed, it can be destroyed
# zfs destroy pool/project/legacy
Example 4: Performing a Rolling Snapshot
The following example shows how to maintain a history of snapshots with a
consistent naming scheme. To keep a week's worth of snapshots, the user
destroys the oldest snapshot, renames the remaining snapshots, and then
creates a new snapshot, as follows:
# zfs destroy -r pool/users@7daysago
# zfs rename -r pool/users@6daysago @7daysago
# zfs rename -r pool/users@5daysago @6daysago
# zfs rename -r pool/users@4daysago @5daysago
# zfs rename -r pool/users@3daysago @4daysago
# zfs rename -r pool/users@2daysago @3daysago
# zfs rename -r pool/users@yesterday @2daysago
# zfs rename -r pool/users@today @yesterday
# zfs snapshot -r pool/users@today
SEE ALSO
zfs-bookmark(8), zfs-clone(8), zfs-destroy(8), zfs-diff(8), zfs-hold(8),
zfs-rename(8), zfs-rollback(8), zfs-send(8)
FreeBSD 15.1-STABLE-HBSD July 11, 2022 ZFS-SNAPSHOT(8)