Computer Backup Tips

Computer backups are important. If you value your time and your data, you really should be doing something about it. It’s easy to get complacent, especially if ‘bad stuff’ never seems to happen to you. But I’m afraid I have some news for you – one day bad stuff is going to happen. Are you ready for it, and do you know how to prepare for it?

What kind of things can happen? Here are a few scenarios:

  • You accidentally delete a file that you really wanted to keep.
  • You somehow corrupt or overwrite a file with garbage or at least the wrong information, and then ‘save’ it.
  • Your hard drive fails.
  • You accidentally format your hard drive when upgrading your system.
  • Someone steals your computer.
  • Your house burns down.
  • A bad guy forces you to hand over your password to your encrypted personal information.

I could go on, but I’m sure that you get the idea! Of course we’re just talking about your own PC here. It gets more complicated if we’re talking about a remote website in a datacentre, or what about at home with multiple computers (one for each member of the family).

Let’s look at some ways of dealing with the problem and provide an analysis of which of the above scenarios you would be protected from.

Technique Allows recovery of deleted or corrupted files? Protects from hard drive failure? Recover from accidental format? Recovers from stolen computer? Comment
Copy file manually to myfile.bak Possibly. If you remembered to save the file before you corrupted or deleted it. No. No. No.  Error prone and unreliable.
Copy file to another disk or partition on your computer. Possibly. If you remembered to save the file before you corrupted or deleted it. If you just used another partition on your main drive, then no. If you used another drive, then yes. If you ‘only’ formatted your main partition, then the data may well be safe. Of course your computer may be unusable now. No. Unless the backup was stored on an external drive that they didn’t spot. Better. Copying files to another drive is about as far as most home users go. It’s not very good really, though.
Use an external drive. Yes. Yes – though if your backup drive fails you will be vulnerable, and have to start the backup regime again. Yes. Maybe – if they don’t steal the backup drive too.
Use a networked drive. Yes. Yes – by the time you are getting around to networked bakcups, you might like to consider using RAID to avoid a single disk failure taking out the system. Yes. Maybe – there is less chance of them taking a second machine or backup device, but don’t bet your life on it.
Use the cloud. Yes Yes. Yes. Yes. If you have a lot of data and a slow Internet connection, this is not going to work.
Burn CD/DVD/Blu-ray copies. Yes Yes. Yes. Yes – try to keep copies off site. Optical media doesn’t last forever.


Important things to remember

  • Do something – anything is better than nothing.
  • Prioritise data over programs. Programs can usually be reinstalled. Photos of your wedding cannot be retaken.
  • Automate it.
  • Make sure your automated backups are reliable.
  • Versioning – some backup systems will store a new backup copy of a file if it has changes that day (for daily backups). You should be able to recover a file from any date back in time, within reason.
  • Store your backups on another storage device – disk / tape / network.
  • Allow for growth.
  • Backup frequency is a trade of between recovering files from minutes, hours, days or weeks ago, and the sheer size of the backup data to be managed.
  • Make sure that you can actually recover files using your backup scheme. It can often not work. In that case it’s a waste of money and effort, and leaves you no better off.


Encryption is the technique for encoding a computer file so that only people with the encryption key can decode it.

There are several typical uses for encryption in the computer field:

  • You might encrypt individual files on your computer to prevent prying eyes from examining them. An example might be a confidential report, or a data file containing all your account passwords.
  • You might encrypt your entire computer hard drive to prevent thieves from gaining access to your data, or to prevent unauthorised use of your computer.
  • There are some encryption tools that you can configure with 2 passwords. If you use one of them it decrypts some decoy data, and if you use the other one, it decrypts the real data. You can use this to satisfy someone who forces you to hand over a password. Just make sure that the decoy data looks ‘good enough’. See Plausible Deniability.

Don’t forget that even if your drive is encrypted, once you have booted and decrypted the machine, if you are connected to the Internet without the protection of a firewall, your data is ripe for the plucking.

Important – If you encrypt your hard drive and forget the password or don’t backup the key meta data and the drive gets corrupted, you will not be able to get it back for love nor money. At least the data is safe. You could consider writing down the password, sealing it in an envelope and giving it to a family member to look after. Or use a password manager, and keep a copy of its data file off site on a CD or thumb drive.

What do we do?

Some of our PCs and laptops are encrypted. Others are not. Those devices that are more likely to be stolen or lost (laptops) or contain valuable or personal data (the file server) are encrypted.

Everyone is encouraged to keep data that they care about on the file server. Everyone gets their own networked drive, plus access to a shared drive. This is automatically backed up. No one needs to worry about it.

Key servers and PCs have most of their main drives backed up (automatically). Taking the long view, it is not necessarily a huge pain to reinstall an operating system. Everyone’s mail is held centrally.

The servers have a RAID system, to help us keep going if a hard drive fails. It gives us a bit of breathing space to get a new drive installed.

We use Bacula for our backups. It can be a bit of a monster to set-up. But now we’ve been through the pain, it’s largely running on automatic pilot.

We save the backups to the networked drive which is OK, because we then burn the backup files to Blu-ray disks and take them off site.

The server and key computers are protected with a UPS, so that if the power goes off, we have some time to shut down in an orderly fashion.

Is it too much hassle? Not when we’ve successfully recovered from a stupid mistake, or hardware or software failure.

Posted in Advice, Backups, Security