zfs-auto-snapshot

Currently, zfsonlinux/zfs-auto-snapshot is no longer being actively developed. However, it remains a powerful and straightforward shell script tool. Therefore, this fork incorporates several features from other branches.

What has changed in this fork:

• Disable default recursive snapshot strategy.
• Use localtime by default instead of UTC.
• Subsequent snapshots will not be aborted even if the pre-snapshot command fails once.
• Add -c option to detect bytes_written firstly in order to prevent duplicate snapshot and potential disk wake-ups.
• Add --default-exclude options to default cron scripts. So only datasets with com.sun:auto-snapshot=true will be snapshotted.

$ zfs-auto-snapshot -h                                                                
Usage: /usr/local/sbin/zfs-auto-snapshot [options] [-l label] <'//' | name [name...]>
  --default-exclude  Exclude datasets if com.sun:auto-snapshot is unset.
  -c, --changed      Snap only if data written > 0.
  -d, --debug        Print debugging messages.
  -e, --event=EVENT  Set the com.sun:auto-snapshot-desc property to EVENT.
      --fast         Use a faster zfs list invocation.
  -n, --dry-run      Print actions without actually doing anything.
  -s, --skip-scrub   Do not snapshot filesystems in scrubbing pools.
  -h, --help         Print this usage message.
  -k, --keep=NUM     Keep NUM recent snapshots and destroy older snapshots.
  -l, --label=LAB    LAB is usually 'hourly', 'daily', or 'monthly'.
  -p, --prefix=PRE   PRE is 'zfs-auto-snap' by default.
  -q, --quiet        Suppress warnings and notices at the console.
      --send-full=F  Send zfs full backup. Unimplemented.
      --send-incr=F  Send zfs incremental backup. Unimplemented.
      --sep=CHAR     Use CHAR to separate date stamps in snapshot names.
  -g, --syslog       Write messages into the system log.
  -r, --recursive    Snapshot named filesystem and all descendants.
  -v, --verbose      Print info messages.
      --destroy-only Only destroy older snapshots, do not create new ones.
      name           Filesystem and volume names, or '//' for all ZFS datasets.

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An alternative implementation of the zfs-auto-snapshot service for Linux that is compatible with zfs-linux and zfs-fuse.

Automatically create, rotate, and destroy periodic ZFS snapshots. This is the utility that creates the @zfs-auto-snap_frequent, @zfs-auto-snap_hourly, @zfs-auto-snap_daily, @zfs-auto-snap_weekly, and @zfs-auto-snap_monthly snapshots if it is installed.

This program is a posixly correct bourne shell script. It depends only on the zfs utilities and cron, and can run in the dash shell.

Installation:

git clone git@github.com:GrayXu/zfs-auto-snapshot.git
cd zfs-auto-snapshot
make install
zfs set com.sun:auto-snapshot=true tank