Mixing RAID with backup

RAID is an additional hurdle for backup and especially for hard drive backup. RAID is a means of connecting multiple hard drives together for data redundancy and/or increased performance. You could have 2 hard drives striped together using RAID 0 for more speed and double the storage or you could connect 3 or more drives together in RAID 5, which increases performance as well as ensures that if one drive fails, no data is lost.

Since a RAID array can exceed the total capacity of any single drive, we may have to create an identical RAID array for backup. If you have 2 drives that are striped together with RAID 0, then it would make sense to create a second RAID 0 array of the same size of hard drives to back up. However, it is better to back up with a single drive if you can do it (much less hassle), so if your RAID 0 array totals 400 GB, go ahead and pick up a single 400 GB hard drive to back up to.

Some people use RAID 1 (mirrored drives) instead of backing up. Their thinking is that since the drives are mirrored, if anything happens to the first drive, the second drive will still be fine. That is true, however, if some corruption happens to the first drive it could easily and instantly be transmitted to the second drive, rendering that “backup” just as corrupted. It is better if a backup is removable and able to be offline most of the time so that its pristine state can be maintained. RAID 1 is fine to have, but it shouldn’t be considered to be on the same level as a backup.

You could also back up to a RAID 1 array of hard drives. The theory would be that if one hard drive fails, you could simply replace that drive and your backup would be completely unaffected. However, if you do that, you’re going to either want an external RAID hard drive enclosure for the backup or a dedicated computer for the backup. Still, this is overkill.

External USB/Firewire drive/enclosure

Instead of installing the hard drive into the computer directly, it is possible to install it into an external USB2 and/or Firewire hard drive enclosure. Once installed, you can just connect the enclosure directly to the computer via the computer’s USB port or Firewire port. If it hasn’t already been partitioned and formatted then you will need to do that via the Disk Manager (Start > Run and type diskmgmt.msc and press ENTER).

While USB2/Firewire is slower than installing the hard drive directly in the computer, it can still push through 20-35 MB/s, which is faster than any of the other options. The big advantage is that now you can remove the drive and take it anywhere. This gives it the portability advantage of other solutions.

There are two different types of enclosures — 2.5″ and 3.5″. 3.5″ enclosures use desktop hard drives (cheaper and larger storage, but require the enclosure be connected to AC power) while 2.5″ enclosures use laptop hard drives (smaller physical size and can be powered by the computer). Which enclosure you choose depends on whether portability or size is more important.

Networked

There are two options for a networked hard drive backup. One is installed in its own networked enclosure (NAS), and the other option is to install the drive in a networked computer and share the drive on the network. An advantage of networked hard drive backup is that the backup is available to anyone on the network, but that is a disadvantage, too, since the backup is now potentially more accessible for corruption by others on the network. This depends entirely on the configuration of the hard drive share. It is nice to be able to have a single network-attached hard drive be the single backup point for several computers on the network, though. It’s a mixed blessing.

A potential disadvantage is speed. Most networks are still 100 Mbps, which is about 8-10 MB/s. Gigabit Ethernet is typically 300-400 Mbps, which is about 30-35 MB/s, but it is much less common.

Internet Service

This is a fairly new backup option. The idea is that you will upload your data to remote servers run by the backup service. Here are some example services (no recommendation being made):

Data Deposit Box – 1 cent per MB per month
WeBackUUp – $100/year for 500 MB. Other options available
VirtualBackup – $80/year for 100 MB. Other options available
StoreMyPC – $10/month for 500 MB. Other options available
First Backup – $10/month (or $90/year) for 500 MB. Other options available

Internet backup Advantages

• Off-site. This is the #1 advantage. Your data can be literally anywhere; it just depends on which service you go with.


• Accessible from anywhere. This is a unique advantage… you can always get quick access to your data no matter where you are. This is especially beneficial if you travel a lot. The 2-3 days you might have to wait to receive and restore your backup from home (if you can even get at that backup at all) would pale in comparison to a downtime of a few hours.


• Durability may be awesome. The reason is that a very good internet backup service will be backing up to a RAID array and be making regular backups themselves. About the only thing they won’t do is an additional off-site backup.

Internet backup Disadvantages

• Expensive. Because it’s a service, you’re billed monthly or annually. Where you could get a 300 GB hard drive for $150, you might not be able to get 1 GB of storage space for one year for that same price.


• Similarly, there is a small storage space. While you can get many gigabytes of storage, it gets very expensive very quickly.


• Very slow transfer. Internet backup is nowhere near as fast as any other backup option. You are limited by your internet connection speed, which for even the fastest ones won’t be more than a few hundred KB/s. A typical cable/DSL internet connection uploads data at 12-35 KB/s. With that kind of performance, you won’t want to be doing a full backup on a daily basis. Data recovery is faster, though, at 150-500 KB/s.


• Security risks. While internet backup services are extremely careful to allay fears of security problems, the potential for an unwanted person to access your data does exist. Your data is being stored on someone else’s computer, and it’s up to them to secure it. It is best to store and transfer the data encrypted over the internet, but even that only raises the barrier of entry; it’s still possible that a compromise could take place.

For people who are always traveling, an internet backup service can be a very good idea so your data is accessible wherever you are, but you can still keep the backup away from your person so should something happen to your computer, your backup will be OK. You will probably want to supplement the Internet backup service with a larger backup medium unless you just don’t have very much data. Otherwise, you could be spending days uploading and downloading your data. Just store the most important stuff on the internet service.

One other option is to get a web host that offers a lot of storage for a fairly low price. Bluehost is one example of this, where you can get 4GB of storage for $6/month. You will have to FTP the files up to the web host, and you’ll have to deal with the potential security issues yourself (encrypting and whatnot), but it is an option that might be cheaper and more flexible than an actual internet backup service. There are also a number of backup softwares out there now that can be configured to upload the backup to an FTP site.