Time Machine Style Backups for Servers with Rsnapshot

A backup for your business (or even personal) data is so essential. Hard drives and other storage media die. It’s just a matter of time. Usually it happens without warning. Files get deleted or overwritten accidentally. The bad scenarios for your data could go on and on. “I was cleaning up and deleted the wrong one.”, etc. Backups are the remedy for that.

One facet of our backup strategy that has been a core piece of our approach is a tool called rsnapshot. Backups take a lot of space and if you make a copy of everything every day…. that becomes a HUGE amount of space. We can’t afford to keep adding more and more storage. Several years ago Apple promoted time machine backups. Where you could restore files to the state they were in last week, last month, etc.

We’re able to implement something very similar on our servers with rsnapshot. Basically it takes a snapshot of the files you want backed up. Then the next run it only adds the change that’s occured. So… it might be possible to keep weeks of backups for 1GB of data in 1.5GB of space. To know exactly how much space you need will depend on the amount of change there is and how many snapshots in time you want to keep.

Rsnapshot can work at several layers. We usually have hourly, daily, weekly and monthly backups. We can choose to save any number of each of those to fine tune space usage. 3 hourly, 3 daily, 3 weekly and 3 monthly backups are decent settings. We have some situations that we keep yearly backups as well and we tweak those numbers based on the data and the storage we have available for backing up.

Rsnapshot can be a great component of a backup strategy and has been one of our favorite tools for years now.