Proxmox Autosnap

A simple script written on python to control zfs proxmox snapshots via pct or qm.

Installing

git clone https://github.com/apprell/proxmox-autosnap.git
ln -s /root/proxmox-autosnap/proxmox-autosnap.py /usr/local/sbin/proxmox-autosnap.py
ln -s /root/proxmox-autosnap/autosnap /etc/cron.d/autosnap
chmod +x /root/proxmox-autosnap/proxmox-autosnap.py

Help

Arguments	Required	Type	Default	Description
vmid	no	list	empty	Space separated list of CT/VM IDs or all.
snap	no	bool	false	Create a snapshot but do not delete anything.
autosnap	no	bool	false	Create a snapshot and delete the old one.
keep	no	int	30	The number of snapshots which should will keep.
label	no	str	daily	One of minute, hourly, daily, weekly, monthly.
clean	no	bool	false	Delete all or selected autosnapshots.
exclude	no	list	empty	Space separated list of CT/VM IDs to exclude from processing.
mute	no	bool	false	Output only errors.
running	no	bool	false	Run only on running vm, skip on stopped.
includevmstate	no	bool	false	Include the VM state in snapshots.
dryrun	no	bool	false	Do not create or delete snapshots, just print the commands.
date-iso-format	no	bool	false	Store snapshots in ISO 8601 format.
date-human-format	no	bool	false	Store snapshots in human readable format.
date-truenas-format	no	bool	false	Store snapshots in TrueNAS format.
sudo	no	bool	false	Launch commands through sudo.
zfs-send-to	no	str	empty	Send a copy of zfs subvolumes to another host via syncoid
tags	no	list	empty	Space separated list of tags
exclude-tags	no	list	empty	Space separated list of tags to exclude
force	no	bool	false	Force removal from the config, even if snapshot deletion fails.
check-free-space	no	bool	false	Verify sufficient storage space before snapshot creation.

proxmox-autosnap.py --help

Examples

# Create a daily snapshot for all VM
proxmox-autosnap.py --snap --vmid all

# Create snapshot only on running vm
proxmox-autosnap.py --snap --vmid all --running

# Create a daily snapshot for selected VM
proxmox-autosnap.py --snap --vmid 100 101 102

# Create a daily snapshot for all VM with the exception of 100 101 102
proxmox-autosnap.py --snap --vmid all --exclude 100 101 102

# Delete all daily autosnapshots for selected VM
proxmox-autosnap.py --clean --vmid 100 101 102 --keep 0

# Create a hourly snapshot for all VM
proxmox-autosnap.py --snap --vmid all --label hourly

# Delete all hourly autosnapshots for all VM
proxmox-autosnap.py --clean --vmid all --label hourly --keep 0

# Create a snapshot name in ISO 8601 format
# Example autodaily_2023_03_22T01_26_23
# It is not necessary to specify the --date-iso-format argument to delete snapshots 
proxmox-autosnap.py --snap --vmid 100 --date-iso-format

# Create a snapshot name in human readable format
# Example auto_daily_250303_134506
# It is not necessary to specify the --date-human-format argument to delete snapshots 
proxmox-autosnap.py --snap --vmid 100 --date-human-format

# Create a snapshot name in TrueNAS format
# Example autodaily20240212194857
# It is not necessary to specify the --date-truenas-format argument to delete snapshots 
proxmox-autosnap.py --snap --vmid 100 --date-truenas-format

# Create a snapshot filtered by tags and exclude tags
# Tags are supported only in Proxmox version 7.3 and above
proxmox-autosnap.py --sudo --snap --tags snap --label hourly
proxmox-autosnap.py --sudo --snap --vmid all --label hourly --exclude-tags nosnap

SUDO

In order to run with sudo argument, you must first create a user and specify minimum accesses for him, for example:

cat /etc/sudoers.d/proxmox-backup

Cmnd_Alias VMLIST = /usr/bin/cat /etc/pve/.vmlist
Cmnd_Alias PCT = /usr/sbin/pct snapshot *, /usr/sbin/pct listsnapshot *, /usr/sbin/pct delsnapshot *
Cmnd_Alias QM = /usr/sbin/qm snapshot *, /usr/sbin/qm listsnapshot *, /usr/sbin/qm delsnapshot *
Cmnd_Alias PVESH = /usr/bin/pvesh get /cluster/resources --type vm --output-format json, /usr/bin/pvesh get /nodes/*/storage --content rootdir --enabled 1 --output-format json, /usr/bin/pvesh get /nodes/*/storage/*/content --output-format json
proxmox-backup ALL=NOPASSWD: VMLIST,PCT,QM,PVESH

After that you can run the script with the argument

proxmox-autosnap.py --snap --vmid 100 --date-iso-format --sudo

zfs-send-to

To use option zfs-send-to, you need to install syncoid, and enable zfs permissions on both local and target hosts. See documentation on configuring zfs allow for syncoid for more information.

Option should be set to [user@]host:zfsdir. All subvolumes of specified VMs will be copied to this path, including rootfs and mpX mount points with backup option enabled on Proxmox.

CRON

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin

# Task for snapshot every hour from 1 through 23.
5 1-23 * * * root /usr/local/sbin/proxmox-autosnap.py --autosnap --vmid all --label hourly --keep 23 --mute

# Task for snapshot every day-of-month from 2 through 31.
5 0 2-31 * * root /usr/local/sbin/proxmox-autosnap.py --autosnap --vmid all --label daily --keep 30 --mute

# Task for snapshot at 00:05 on day-of-month 1.
5 0 1 * * root /usr/local/sbin/proxmox-autosnap.py --autosnap --vmid all --label monthly --keep 3 --mute

# Task for snapshot every hour from 1 through 23.
5 1-23 * * * root /usr/bin/python3 /etc/pve/bin/autosnap/proxmox-autosnap.py --autosnap --vmid all --label hourly --keep 15 --mute

# Task for snapshot every day-of-month from 2 through 31.
5 0 2-31 * * root /usr/bin/python3 /etc/pve/bin/autosnap/proxmox-autosnap.py --autosnap --vmid all --label daily  --keep  7 --mute

Warning

If the script is stored in /etc/pve/, it must be executed with python or python3, as this directory does not support the executable attribute.

LVM

When using this script with LVM-based storage, it's important to be aware that every time an LVM snapshot is created, LVM stores a backup of the volume group configuration in the /etc/lvm/archive directory. If the snapshot script is executed frequently (e.g., hourly), this directory can accumulate a large number of files over time, potentially consuming significant disk space.

To mitigate this, consider setting up a cron job or other cleanup mechanism to periodically remove older files from /etc/lvm/archive. For example:

# Remove LVM archive files older than 7 days
find /etc/lvm/archive -type f -mtime +7 -delete

At the moment, skipping LVM snapshots entirely is not feasible, especially in environments where virtual machines or containers might use a mix of LVM and ZFS storage backends. Be sure to monitor this directory and adjust your cleanup policy accordingly.