From my last posting about ZFS “Fun with ZFS send and receive” we see that the ZFS commands are really easy to use but very powerful, because of this I find it easy to write scripts to do the things I need. Here is some code that I use for snapshots, it’s written in python but can be ported to anything as it’s taking command line output and parsing info for what it needs.

Making Snapshots:⌗

This code is used to make snapshots of all the file systems on a zpool. Just edit the zpoolName to be the name of the zpool you want to work with. The main command line in code is zfs list -o name | grep zpoolName which outputs a list of filesystems onto the zpool which is used in the code to make snapshots with a timestamp in the snapshots name.

#!/usr/local/bin/python
#Used to make snapshot of all the file systems on a zpool.
import commands
import subprocess
import time
import os
timestamp = time.strftime("%Y%m%d-%H%M")
zpoolName = "storage"
zfsList = commands.getoutput("zfs list -o name | grep %s/" % zpoolName)
for zfsFileSystems in zfsList.split("\n"):
print "Snapshoting-> %s" % (zfsFileSystems)
commands.getoutput("zfs snapshot %s@%s" % (zfsFileSystems, timestamp))
view raw zfs_make_snapshots.py hosted with ❤ by GitHub

Removing Snapshots:⌗

This code is paired with the one that takes the snapshots. It will remove old snapshots after a set number of days by reading the timestamp in the snapshots name. The main command here is zfs list -H -t snapshot | awk '{print $1}' | grep zpoolName which should output a list of all the snapshots on the zpoolName.

#!/usr/local/bin/python
#Used to remove old snapshots of all the file systems on a zpool.
import commands
import subprocess
import time
import datetime
now = datetime.datetime.now()
zpoolName = "storage"
zfsList = commands.getoutput("zfs list -H -t snapshot | awk '{print $1}' | grep %s/" % zpoolName)
for zfsSnapshot in zfsList.split("\n"):
dateSnapshot = datetime.datetime.strptime(zfsSnapshot.split("@")[1], "%Y%m%d-%H%M")
if (now - dateSnapshot) >= datetime.timedelta(days = 30):
print "Removing-> %s" % (zfsSnapshot)
commands.getoutput("zfs destroy %s" % (zfsSnapshot))
view raw zfs_remove_snapshots.py hosted with ❤ by GitHub

Open to comments or any ideas to make my code better.