Backups

Backups are a subject most of us like to ignore. When we talk about "backups" in the context of a computer system we are referring to the process of taking a copy of some or all of the information on a computer for use in the event of some problem. Therein lies the problem - most of us prefer to think that problems occur to other people and not to us. Sadly, statistics will win in the end. Each person who looks after a computer system needs to consider backups and have some sort of strategy. (OK - "I don't do backups" does count as a strategy - it's just not a very good one).

What do Backups Do for Us?

The reason most people forget about backups is that they are only useful when something goes wrong. The times we need our backups are when we have just accidentally deleted an important file and want it back, when someone or something else has deleted files we want back or when a hard disk fails or is lost to us and we want to setup a new disk like the last one. (All disks have something known as MTBF or Mean Time Between Failures, the average time we have before something goes wrong.) Even if hardware failure is not the cause, computers are vulnerable to being stolen or can be irreparably damaged by fire, dropping, water and so on. In all cases once it's happened it's too late to start your backup strategy - this is something you should have in place to enable you to cope with these events.

Types of Backup

There are three main types of backup, Full, Incremental and Partial. They refer to what is backed up.

A full backup is a copy of everything on a disk or on a system. (By "system" we mean the whole computer, specifically in this context all the hard disks in the computer). It is the most comprehensive and thus time consuming type of backup.

An incremental backup is a backup which copies only those files which have changed since the last backup (or the last full backup). The idea here is that you take a full backup, then each day (or whatever interval you choose) you take an incremental backup of just those items which have changed. In the event of a failure you first restore the full backup and then you add the items which changed after the full backup was taken by restoring the incremental backup(s).

A partial backup is a backup of just part of the system. This is useful if you would only really need to restore certain files in the event of a disaster rather than the entire system.

Creating your backup strategy

To create your own strategy you need a few simple questions you need to ask yourself:

1) What information from my system would be really crucial to me if my system failed? If your computer is used for nothing more than games then maybe you'll want to save the high score tables but that's about it. On the other hand if you run your small business from your computer then all your business records plus perhaps your emails will need to be backed up. Most readers of this site will be somewhere in the middle - they'll have various items on the PC which are important to them - digital photos, downloaded music, emails and the like.

2) How many days activity is it acceptable to loose in the event of a failure? This tells us the maximum period we can go between backups; this will depend on how often you change the data and how much you care about each change. For most home users once a week or even once a month may be sufficient.

3) How much effort am I prepared to put in to get my system or replacement system back to working order if the hard disk fails? If you have only a partial backup then you will need to re-install Windows plus all the other applications you have. This can take many hours, compared to restoring a full backup which might take one hour.

My recommendation would be that almost everyone should take a full backup regularly, say once a month, and then also take an incremental or partial backup once a week. If you're a business user change this to a full backup once a week and an incremental each working day.

Backup Media

We now come to the important topic of what we are going to back up to, that is on what media we will store the backup. Ideal media are seperate from the disk or data being backed up, have a long life, can be stored away from the system containing the data and are practical to use. By practical to use I mean that there is little point in deciding to back up your 80GB disk every day if you only have floppy disks to use as a backup medium. Swapping in and out the 69,500 floppy disks it would require if your disk were full would be tedious in the extreme and you'd need an extra room in your house to store all the disks!

The ability to store the backup media away from the system it holds the backup for provides protection if the worst happens - a fire destroys the computer and the room it is in or a thief steals the machine itself. If we have used a second internal hard disk for our backup then loosing the computer means we also loose the backup - a double disaster.

Probably the best media for most people are writeable DVDs. Each DVD can hold around 4.7 GB, (more if using the DVD-RAM format), has a long life, is easy to transport and is normally unharmed if dropped. It is also fairly cheap - a point not to be dismissed too lightly. If you have a relatively small amount of data then the same argument can be put forward for writable CDs except the capacity is around 650-700MB.

Backup Tools

So what tools should we use for backing up our system? This question should be answered in terms of the full backup because that's the more complicated part and the most time consuming. What we require from this tool is the ability to create a copy of our entire system in as quick and painless a way as possible. This is important because something complicated or time consuming is unlikely to get done regularly. Equally important is the abililty to restore our system to the state it was at when we took the backup (people tend to forget this bit because we all hope never to have to do it...).

Windows Backup

Your Windows XP system comes with the Microsoft Backup tool. This tool is installed as standard with Windows XP Pro but has to be installed as a separate step in the Home version. (There is no additional charge). To install Backup on the home version, put your Windows XP Home Edition CD-ROM into your CD drive and navigate to the folder:
  <CD-ROM Drive>:\VALUEADD\MSFT\NTBACKUP.
Double-click the Ntbackup.msi file to start a wizard that installs Backup. When it finishes click "Finish" to close the wizard. Once installed the Backup tool is available from the Control Panel, Performance and Maintenance icon or from Start menu via the navigation:
Programs Menu->Accessories->System Tools.

Windows Backup works OK and is of course free (always a positive), but it does not have a true image mode backup capability. By that we mean that the system cannot take a complete picture of the disk and restore another disk to look *exactly* like the original. For that we have to look at third party tools.

Third Party Backup Tools

There are a number of good third party backup tools available at a range of prices. Probably the best known are Norton Ghost and PowerQuest's DriveImage. Interestingly Norton (actually Symantec these days) have bought PowerQuest, so only Ghost is left of the two, but Symantec say they have incorporated the best of DriveImage into Ghost. Having investigated the latest versions of these products we have decided that they have become more bloated and difficult to use than they need to be. We are therefore recommending a newer product, Acronis True Image. (You can get a free 15 day trial version by using this link.) This product is quick and easy to use and costs less than Ghost. We will be running some tests to compare True Image with Norton Ghost and Windows Backup. We'll update this page with the information and send an alert to subscribers to our Newsletter when we've done it.