Backups: Everything You Need to Know

Let’s face it, it’s really not about your computer. It’s about your files! Your email, your pictures, your documents, your music, your movies…those are what’s really important. If you have a proper backup, even if your computer is lost, stolen, destroyed, or self-destructs, your data is safe if you have a backup. For that reason, everyone should back up their computer.

There are several kinds of backups, and you should know the differences.

Mirror Backups

Mirror backups initially back up your entire internal drive to a backup drive, and subsequent backups copy whatever has changed since the previous backup. At the end of a mirror backup, the backup drive is identical to the internal drive.

Files you have added to the internal drive since the last backup will be added to the backup drive. Files that you have updated since the last backup will be copied to the backup drive, replacing the older versions. Files that you have deleted on the internal drive will be deleted from the backup drive.

The upside of a mirror backup is that you can boot up your computer from the backup drive, just as you can from the internal drive. If the internal drive fails, you can boot from the backup drive and be 100% up to date (as of the last backup). And you can continue working that way until the internal drive can be replaced. If your entire computer fails, or you get a new one, you can boot that computer from the backup drive, too…and the new computer will have everything you had on the old computer.

The downside (or limitation) of a mirror backup is that if need to recover a file you deleted a day, week, or month ago, there is no way to recover it…if it was deleted from your computer, it was deleted from the backup too.

Archival Backups

Archival backups also back up your entire internal drive the first time a backup occurs. And subsequently they back up whatever has changed since the previous backup…without deleting the older or deleted files.

The upside of an archival backup is that you can recover older versions of files you’ve since change, or files you deleted from the internal drive a day, a week, or even a month ago.

The downside of an archival backup is that you can’t boot up your computer from this kind of backup…if the drive in your computer fails, you’d have to do a complete restore before you can boot up, which takes time.

Backup Software

Time Machine, which is built into all versions of MacOS since 10.5, is excellent archival backup software. There is nothing to buy (other than the backup drive). After the initial backup, it backs up hourly in the background, so if your internal drive were to fail, once you restore to the replacement drive you’d be up to date within 1 hour or less of the time the internal drive failed.

For mirror backups, you must use third party software. Our favorite is Carbon Copy Cloner. You can set Carbon Copy Cloner to do regular backups on a schedule. We usually set Carbon Copy Cloner to back up daily at an hour when it won’t interfere with your normal work.

Backup Locations

An external drive is the most common place for your backup. The drive directly connects to your computer by USB or Thunderbolt, and they can be used for either Time Machine (archival) or Carbon Copy Cloner (mirror) backups.

If you’re going to use an external drive for a mirror backup, it’s capacity must at least match the capacity of the drive being backed up. If you’re using the drive for an archival backup, the drive should be at least twice the size of the drive being backed up…to leave room for the deleted and older versions of files to remain even when they’ve been trashed on the internal drive.

The upside of using an external drive is that it remains in your possession all the time.

The downside is that if you keep the backup drive where the computer is, and there is a catastrophe like a fire, flood, or theft, the backup drive will be damaged or lost just like the computer, which brings us to…

A cloud server. There are companies that specialize in providing space on their servers to which you can backup your entire computer…via the internet. The common providers are BackBlaze, Carbonite, and CrashPlan (also called Code 42), and there are others. Cloud server backups are archival backups.

Cloud Backups

Cloud backups are archival backups that are saved, though the internet, to the internet based server of the cloud backup company. Because they are not physically within your location, even if catastrophe strikes, your backup is entirely save…and the backup company will send it to you on an external drive from which you can restore it to your replacement computer.

Our favorite online backup is BackBlaze. It is easy to set up and use, and costs $7.00 a month per computer being backed up, payable annually. The monthly price is higher if you choose to pay monthly, which we don’t recommend.

Like with Time Machine, the initial backup may take a while, depending on how much data needs to be copied. Thereafter, backups are quick, since only what’s changed since the last backup must be copied. And the backups take place in the background throughout the day.

If you need to recover one or two folders, or a few files, from your cloud backup, you can do that right through the BackBlaze application. If you need to restore your entire computer, or recover gigabytes of data, BackBlaze will send you your entire backup on an external drive…overnight.

You can learn more about BackBlaze by going to the BackBlaze web site. There are many other cloud backup companies, too! Carbonite, CrashPlan, SugarSync, iDrive…but having tried them, we find BackBlaze the least expensive and easiest to implement and use.

Backup strategies

Our favorite backup strategy is to combine a mirror backup with a BackBlaze backup. That way, you have a bootable copy of your internal drive in your possession that you can use to boot up your computer if the internal drive fails, but you also have an off-site backup from which you can recover everything in case of catastrophe.

You can accomplish something similar by combining a mirror backup with a Time Machine backup…but in that case, both backups are physically in your possession, and both could be destroyed in a catastrophe unless you take one of those backups off site.

Simplest: Do regular mirror backups to an external hard drive. This protects if your internal drive fail. If you keep two mirror backups, and take one off premises each day (swapping them on alternate days), you’ll be protected against internal drive failure and a catastrophe that destroys you computer and the backup drive on premises. The downside of this strategy, though, that you have to remember to swap the drives and take one with you every day.

Questions? Contact us!