The best home backup plan options - Part 3: External drive backup

The best home backup plan options: Part 3

Now things start to get more interesting and viable. External drive backup has been the primary method used for proper backups for the past two decades. This type of backup involves one or more hard drives which are independent of your primary operating system or boot drive. It's not limited to hard drives, magnetic tape and other forms apply as well, but since we're talking about home backup solutions we'll stick to standard hard drives.

[Bullet-proof backups: When you absolutely can't lose any data and How to buy the best portable hard drive]


Connection Types

The first consideration for external drive backup is how the external drive will be connected to the machine or machines you'd like to back up.

The three main possibilities are:

  • Additional internal drive

  • USB/Firewire/Thunderbolt connected external drive

  • Network attached storage (NAS)

Additional internal drive

This method involves opening the case on your computer and adding an additional hard drive to your system. This is the least recommended solution as the backup disk is physically connected to the motherboard inside of your computer. This prevents you from easily moving the backup disk, and should a disaster occur, you'll lose the backup disk as well as your computer. The upside to this method is that the file transfer rate is as fast as it can be for your hard drive.

USB/Firewire/Thunderbolt connected external drive

Using this method, you connect an external drive that is generally in an enclosure to your computer using a cable and port such as USB,Firewire, or Thunderbolt on recent Macs. This gives you the ability to move the drive away from the computers you're backing up giving you an added level of safety.

If you don't have thunderbolt and your computer has USB 3.0 ports available (they are usually colored blue), I highly recommend getting a USB 3.0 compatible external drive as the transfer speed is nearly as fast as an internal drive (5 Gbit/s).

Some options for each connection type over at Amazon if you're interested:

Network attached storage (NAS)

Network attached storage is similar to the USB/Firewire/Thunderbolt option but instead of connecting the drive to your computer directly, you connect the external drive to your home network using an ethernet cable or wi-fi.

In order to use this method, you first need a home network. This only makes sense if you have more than one computer connected to the internet in your house. If you don't then you should choose the USB route. If you do, then you likely already have a home network. The only component that is required for your home network is a router.

The big benefit to a NAS device is that it's accessible to all of the machines on your network so you get a common location for the whole family to backup their computers to. It also allows you to stash the drive away somewhere out of sight as long as it's connected to the network. Finally, many NAS devices come with extra features you may find useful, such as a media server.

This option can be more costly as the enclosures generally require you to bring your own disks, meaning you buy them separately from the enclosure.


The second consideration involves protecting your backups. You have the option of using multiple hard drives in what is known as a RAID configuration. RAID stands for Redundant Array of Inexpensive (or independent) Disks. There are several RAID configurations but for most home backup purposes the RAID 1 (mirroring) configuration is appropriate. If you need higher performance, you should explore a RAID 0+1 configuration.

With a RAID 1 setup you need 2 hard drives. An exact copy of the data is mirrored to each drive in the array. The array continues to operate as long as at least one drive is functioning. Once you replace the failed drive, the data will be restored to it and you'll be protected again. This configuration has a fault tolerance of n-1 disk failures.

A RAID 1 setup can be accomplished using any of the above mentioned external disk connection types. For the additional internal disk option your motherboard will either need to have a RAID controller or you'll need to use a software RAID controller (built into most operating systems). For the external enclosure and NAS options, simply choose an enclosure that supports multiple disks and RAID.

Recommended Devices

The best option in my opinion is the Synology DiskStation 2-bay diskless system. This device has all the features you need and is both a NAS device and a USB 2.0 device. It doubles as a media server and includes backup software as well as nice extras such as mobile apps and data encryption. At $199 without disks, it's not exactly the cheapest option but it will definitely make your life easier when it comes to automated backups of all the computers in your house.

For a less expensive alternative that gives up the RAID capabilities, see the Synology 1-Bay NAS Server. For $149, you get all of the features of the 2-bay system except for the data redundancy. The cost difference should show you the value in choosing the 2-bay option.

Of course you're free to explore the thousands of bare bones drive enclosures out there and simply add your own disks, but keep in mind that many of them will require a bit of technical expertise to get running and stay running. In my experience, the less you have to think about backing up and the more automated it is, the more likely it is to actually get done.


A big concern when it comes to external drive backup is that most often the external drive is kept in the same location (i.e. your house) as the original data. Should a flood or fire occur, everything is still lost.

One way the co-location problem can be solved is the way it's been done forever in IT shops. You basically operate on a backup cycle with extra storage units. Back 8 years ago I used to do this on magnetic tape, i'd back up everything onto 8 tapes, one for each day of the week plus 1 weekly archive. Every day I would take home yesterdays tape (away from the office) and the next day I would bring it back and take the following day's tape and do the same. That way if the building exploded I always had a backup offsite. You could do something similar by building 2 backup units and just take one elsewhere. Periodically swap them out to keep each close to synchronized.

Another more convenient option is a service called Sneaker Backup. Warning - this appears to be a pretty early stage startup. This company turns this lo-tech co-location solution into a NetFlix-esque process. Periodically they will mail you an external drive to plug into your computer along with a prepaid return box. You make a backup of your system and send the encrypted disk back to them for storage off-site. If you need your backup data it can be downloaded from their servers or they will overnight you a hard drive with your backup on it. It's a pretty interesting concept at $24/month.


Finally, some solid options for backing up your entire home. Use one of these options either with the devices included backup software or using one of the backup programs outlined in Part 2 of this series.

Next up I'll talk about cloud backup options.

Next - Part 4: Cloud based backup

Never forget:

Other posts in this series

  • Part 1: The Basics
  • Part 2: Same machine backup
  • Part 3: External drive backup

  • Part 4: Cloud based backup
  • Part 5: A complete backup strategy

This story, "The best home backup plan options - Part 3: External drive backup" was originally published by ITworld.

Copyright © 2012 IDG Communications, Inc.

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