A backup plan, part 2: What method will work for you?

In last week’s column, I discussed the various forms of data storage. Branching off from that, we can now better understand various backup methods.

I encourage you to refresh your memory by re-reading last week’s column. There will be information at the end of this column that tells you where to find my archive of Interpreting Tech columns.

When it comes to backups, there are really only two types commonly used: file and image.

A file backup is the form most people are familiar with. In simple terms, it’s just a copy of the files you want to save, frequently retaining the same directory structure and file type as the original data. Various software programs perform a file backup in a handful of ways, from a simple file copy to a compressed archive.

There are plenty of free programs out there that perform this task quite well. For those running a flavor from Microsoft, the built-in Windows Backup for XP and above works pretty well. Another utility I love is Karen’s Replicator. It’s easy to use and quite powerful.

An “image” backup is less familiar but is actually the best backup method of the two if you’re attempting to rebuild from a failed hard drive or system crash. Instead of just copying the “raw files” as they sit, it also copies hidden parts of the operating system, as well as files that are in use and otherwise locked, creating a fully recoverable backup.

The common software applications are Windows Backup for Vista and Windows 7 only, Acronis TrueImage and Norton Ghost.

If you’re running OS X on a Mac, one of the best tools for image backup is Carbon Copy Cloner.

With the simple file backup, it is important to be aware of “locked” files. These files are currently open and cannot be accessed by the operating system or backup program to make a copy.

For example, if you leave your accounting software open during a file backup, it likely won’t copy the database file that contains all your data. Likewise, if your e-mail client is open, your e-mails might not get copied.

The “image” method bypasses the locked-file problem. In Windows, this is called a “shadow copy” or “volume shadow service.” This nifty feature can capture information in memory (locked and in-use) and store it in an accessible area, allowing the backup software to grab it and stick it where it belongs.

Both methods can be used quite effectively in all types of digital storage. The simple file copy usually results in a smaller backup-file size, allowing it to fit on more types of media, such as a CD/DVD or a USB flash drive. The image method stores everything on the system and can grow quite large.

Depending on the size of your data, you may need larger backup media such as an external hard drive.

No matter what method you use, you should always have your data in at least two places, preferably in different physical locations, to avoid loss due to fire or theft. Frequently, businesses will rotate external backup devices daily, allowing them to have a backup off-site at all times. Some even take advantage of online backup solutions, though these can be limited by available storage size and Internet bandwidth.

The last important factor when dealing with backups is automation. When people forget or get lazy, manual backups often don’t happen. Removing the human element can make the difference between retaining your life’s memories or not.

Any good backup software package will include a method for scheduling a backup at a time and in a way that works best for you.