There are utilities that can do exactly what you’re requesting. It’s called cloning and what it does is a sector-by-sector copy of one hard drive to another. The two hard drives need to be identical or very close to it for a clone to work.
You then have a fully cloned copy of the original hard drive that you can swap into the internal hard drive’s place if something happens.
What you’re asking about is cloning software. Many backup programs (like Macrium Reflect) have the option to clone a drive. But I don’t really like the idea of cloning drives. Here’s why.
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Cloning or external drives
Certain types of machine failures will actually take out one or more of the internal hard drives. Now, if you happen to have both of your drives installed at that time, then you could potentially lose your primary drive and your backup at once.
I’m not a big fan of that. It seems too risky and to be honest, cloning is probably overkill.
What I do recommend – especially if you’ve got these two additional 80 GB drives – is put each of those in an USB enclosure, so that they effectively become 80 GB external drives.
I would then use imaging backup software; this will backup only the data that’s on your hard drive, but it will backup all of it. Even if it were full, your 80 GB hard drive is not necessarily going to take up 80 GB when it gets backed up to one of these other drives.
An image backup copies the data that’s on your hard drive, and compresses it at the same time.
You can then also start doing incremental backups. So let’s say your first full backup is something like 40 GB. The next incremental backup will only backup those files that have changed. So that means on one of your 80 GB drives, you could potentially get something like a 40 GB starting point and then a number of 1,2,5 or 10 GB incremental backups depending on how much has changed since the prior backup . That seems like a much more robust approach to keeping that machine backed up.
Now, another thing I’m not a fan of is incremental backups so the other thing you can do is automate it.
Automate with Macrium Reflect
Macrium Reflect can automate your image backups so you don’t have to worry about it. That’s a great way to make sure that if something happens to your system, you’ve got the other 80 GB drive that had a perhaps slightly older backup available somewhere else.
Well, what happens now when your system fails?
You start by replacing the 80 GB drive in your machine. Yes, you could replace it with one of the spares that you have. Because you’re using those for backup, it won’t be a direct replacement. What I would recommend you do is get a true replacement (a bigger one, if you like), then use Macrium Reflect to stream or restore the backup image from one of the old external drives on to your new hard drive. Then, it will be as good as new.
Ultimately, you have several options here. Yes, you can do exactly what you’ve described. But I prefer that you move to a more traditional image backup situation: use your external drives as backup drives, replace your C: drive if it ever fails, and use your images to restore.