xs-backup

Backup script for Citrix XenServer, based on the original script by Mark Round github@markround.com:

http://www.markround.com/snapback

https://github.com/markround/XenServer-snapshot-backup

Overview

The script creates a snapshot of a running VM on a configurable schedule, and then creates a template from this snapshot. It will copy all these backup templates over to a configurable storage repository, and then clean up any old backups according to a specified retention policy. These backups are full backups, so if you have a 10GB VM and keep 7 previous copies you will need a total of 80GB disk space on your backup VM. Non-running VMs, and those not configured (as detailed below) will be skipped.

Important: See KB CTX123400. After backing up each VM, you will end up with a new VDI, so you may need to manually coalesce your VDIs again to reclaim disk space. This appears to have been fixed in 5.6FP1, however.

Installation and Usage

First, copy the script to your Xenserver pool master, and make it executable. A good location for this is

/usr/local/bin/xs-snapback

THIS SECTION IS CURRENTLY OUT OF DATE

Next, create a cron entry for the script - to make it run daily just after 1AM, you'd create /etc/cron.d/xs-backup with the following contents:

2 1 * * * root /usr/local/bin/xs-snapback.sh > /var/log/xs-snapback.log 2>&1

TODO: explain SR as cmd line opt

XenCenter Configuration

Lastly, you need to configure your backup and retention policy for your VMs. In Xencenter, right click your VM, and select "Properties". Click on "Custom Fields", and then "Edit Custom Fields". You should add two text fields :

• backup

  Can be one of daily, weekly, or monthly. If it is set to weekly, it will by default run on a Sunday, and if it set to monthly, it will run on the first Sunday of the month.

• retain

  How many previous backups (in addition to the currently running backup) to keep. So, setting this to a value of "2" would mean that after a backup has run, you would end up with 3 backups in total.

The script will look for these fields when it is run, and will skip any VM that doesn't have them set. You can also see them in the XenCenter summary and properties for the VM.

You can now either run the script manually, or wait until the cron job kicks off. It will produce a detailed log to the console (or log file if run through cron), and when it's finished, you'll see your template backup VMs listed in Xencenter.

If you find that this clutters up the Xencenter view a little, you can always hide them (View->Server View->Custom Templates).

To restore a VM from a backup, just right click, and choose "New template from backup".