ZFS autobackup

Introduction

ZFS autobackup is used to periodicly backup ZFS filesystems to other locations. This is done using the very effcient zfs send and receive commands.

It has the following features:

• Automaticly selects filesystems to backup by looking at a simple ZFS property.
• Creates consistent snapshots.
• Multiple backups modes:
• "push" local data to a backup-server via SSH.
• "pull" remote data from a server via SSH and backup it locally.
• Backup local data on the same server.
• Can be scheduled via a simple cronjob or run directly from commandline.
• Backups and snapshots can be named to prevent conflicts. (multiple backups from and to the same filesystems are no problem)
• Always creates new snapshots, even if the previous backup was aborted.
• Checks everything and aborts on errors.
• Ability to 'finish' aborted backups to see what goes wrong.
• Easy to debug and has a test-mode. Actual unix commands are printed.
• Easy installation:
• Only one host needs the zfs_autobackup script. The other host just needs ssh and the zfs command.
• Written in python and uses zfs-commands, no 3rd party dependencys or libraries.

Example usage

In this example we're going to backup a SmartOS machine called smartos01 to our fileserver called fs1.

Its important to choose a uniq and consistent backup name. In this case we name our backup: smartos01_fs1.

Select filesystems to backup

On the source zfs system set the autobackup:smartos01_fs1 zfs property to true.

[root@smartos01 ~]# zfs set autobackup:smartos01_fs1=true zones
[root@smartos01 ~]# zfs get -t filesystem autobackup:smartos01_fs1
NAME                                                PROPERTY                  VALUE                     SOURCE
zones                                               autobackup:smartos01_fs1  true                      local
zones/1eb33958-72c1-11e4-af42-ff0790f603dd          autobackup:smartos01_fs1  true                      inherited from zones
zones/3c71a6cd-6857-407c-880c-09225ce4208e          autobackup:smartos01_fs1  true                      inherited from zones
zones/3c905e49-81c0-4a5a-91c3-fc7996f97d47          autobackup:smartos01_fs1  true                      inherited from zones
...

Because we dont want to backup everything, we can exclude certain filesystem by setting the property to false:

[root@smartos01 ~]# zfs set autobackup:smartos01_fs1=false zones/backup
[root@smartos01 ~]# zfs get -t filesystem autobackup:smartos01_fs1
NAME                                                PROPERTY                  VALUE                     SOURCE
zones                                               autobackup:smartos01_fs1  true                      local
zones/1eb33958-72c1-11e4-af42-ff0790f603dd          autobackup:smartos01_fs1  true                      inherited from zones
...
zones/backup                                        autobackup:smartos01_fs1  false                     local
zones/backup/fs1                                    autobackup:smartos01_fs1  false                     inherited from zones/backup
...

Running zfs_autobackup