This tutorial by user iceflatline shows us how to improve offsite backups by using ZFS replication features in FreeBSD.
Recently I decided to improve the reliability of my file system backups by using the data replication capabilities inherent in the FreeBSD Zettabyte File System (ZFS). ZFS provides a built-in serialization feature that can send a stream representation of a ZFS file system (Which ZFS refers to as a “dataset”) to standard output. Using this technique, it is possible to not only store the dataset(s) on another ZFS storage pool (zpool) connected to the local system, but also to send it over a network to another FreeBSD system. ZFS dataset snapshots serve as the basis for this replication, and the essential ZFS commands used for replicating the data are zfs send and zfs receive.
This post describes how I used this ZFS feature to perform replication of ZFS dataset snapshots from my home FreeBSD server to another FreeBSD machine located offsite. I’ll also discuss how I manage the quantity of snapshots stored locally and offsite, as well as a couple of options for recovering my files should it become necessary.
For purposes of example, I’ll refer to the FreeBSD system hosting the snapshots I want to send as “server”, and the offsite FreeBSD system that I will send snapshots to as “backup”. Unless otherwise noted, all steps were performed as the user root. However a non-root user, “iceflatline”, was created on both machines and is used for many of the commands. The versions for the software used in this post were as follows:
- FreeBSD 10.1-RELEASE
On server I had created a simple mirror vdev for my zpool consisting of (2) two terabyte disks. The mirror and the zpool were created using the following commands: