Computers are easily replaceable, but data is precious. Here are some tips to help you ensure that your data isn’t lost if your machine melts down.
Backup set A, Backup set B
Make two backups, not just one. If you have problems while overwriting a previous backup, this will ensure you still have one backup copy available, as well as the original data. Three copies of the data (the original and backup sets A and B) are much safer than just two.
Optical Media
CDs or DVDs are not recommended for backing up irreplaceable data. Unless the blank optical disk is of high quality, and is handled and stored with great care, data written to it may be lost or the optical disk may become unreadable.
USB flash Drives
USB flash Drives are suitable for backing up smaller amounts of data. They are reasonably robust, but can only sustain a limited number of write cycles. This limit may be about 1,000,000 writes, but please notice that may not mean to each memory cell, so a common USB flash drive life may be shorter, perhaps as low as 50,000 writes. Despite this limit USB flash drives may be relied upon for a few years, depending on the cycle of use.
USB external hard drives
USB external hard drives are suitable for backing up many gigabytes of data. They are fast and reasonably robust. If they are not dropped, USB external hard drives can be relied upon for a few years, depending on the drive specifications and the level of use.
Encrypt data with TrueCrypt
If your data is subject to the Data Protection Act, or otherwise sensitive or secret, it may be worth using TrueCrypt (downloaded from here). This application can be used to encrypt your data, or even the entire data drive. If you deal with data covered by the Data Protection Act, you should speak to Brunel’s Data Protection Officer to confirm you’re handling the data properly.
Offsite backup
One set of backups should be kept in a separate physical location from the computer that stores the original data. In this manner disasters such as fires, floods, etc may destroy the computer with the original data, and Backup set A, but Backup set B is highly unlikely to also be affected. For this reason all backup data from the Brunel network is stored in two separate buildings on campus.
Test restore
It is important to regularly run a test restore from your backup, to prove the media is still valid. Eventually the backup media will reach the end of its useful life, at which point it must be replaced by a fresh data storage device.
Backup software
If you use a proprietary backup program, the licence must still be valid when you finally need to restore the data. If the backup software is discontinued, you may lose access to your data. It is safest to simply copy your data, to guarantee that you will not be denied access due to ‘vendor lock-in.
File formats
You should consider carefully which file formats you choose to store, and ensure you will still be able to read them in the future. If you have old documents saved using e.g. Wordperfect6.1 for DOS, you must be able to run that program to be certain that you can use that data after it’s restored.
Data loss
Data loss refers to the unexpected loss of data or information, this can occur for many reasons including hardware failure, software failure, or power failure. For this reason the Computer Centre strongly advises against the practice of saving data to the local drives of your PC. Users are encouraged to always save data to their network drive or an external source such as a USB flash drive, DVD or hard drive.If you suffer from data loss on the local drives of your PC the PC Support team may be able to advise on the best course of action but are currently unable to provide a data recovery service.