Planning a backup strategy |
If you are inexperienced with backup, restore, and disk imaging, you can review the following advice before you start backing up systems. It provides guidance and tips for you to consider before setting up a backup regime with the aim of rapid restoration or even disaster recovery. If you carry out all the recommendations given in this topic you should be able to recover from most system based problems and also appreciate the amount of time recovery from various problems would take. In addition, by knowing recovery times you can start to plan alternatives that are better suited to your circumstances.
A good backup cycle is essential for three main reasons:-
To protect your computer from sudden failure
To give you the ability to recover historical data
To optimize the use of available storage space
It is recommended that you create at least one image file containing all your backed up partitions, files and folders and a Macrium Reflect Rescue CD that contains a boot loader and user interface allowing you to locate and restore your images. Once you start updating and storing more data, you may want to create an image periodically, say every day, week or month depending on the value of your data.
In a typical periodic backup cycle you may choose to use two or more external USB drives to store the backed up images. These can be rotated on a weekly basis allowing the external drive that isn't currently in use can be stored off-site for extra security. It is then a question of using a combination of full, incremental and differential backups to achieve the optimum level of coverage that suites your needs.
Full backup - Performing a full backup ensures that Macrium Reflect copies all the selected partitions, files and folders in to the image file
Incremental backup - This stores only the changes make to files since the last incremental backup or if none exist, the last full backup. When restoring incremental backups, Macrium Reflect works out which revision of files should be restored based on the subsequent incremental backups and the original full backup.
Differential backup - Stores only the changes made to files since the last full backup. As a result, differential images will get larger as the time from when the full backup was taken increases.
There is no definitive configuration for scheduling your backups, but if your data is valuable to you, backing up regularly will ensure that any system failure or data loss will have the smallest impact in terms of lost work. If we take the idea of having two external USB disks that are rotated we may choose to implement the following backup cycle
Week 1
Take a full backup of the system over the weekend before week one onto external disk 1
Make an incremental backup of the system each night onto external disk 1
On Friday evening, send disk 1 off side and use external disk 2 to make a full backup over the weekend
Week 2
Repeat the process as outlined in week 1 and then rotate the disks again.
In order to ensure that the external disks do not become full, after the two week cycle is complete, disk 1's images can be deleted before taking a new full image.
This process has the advantage that if anyone were to loose their work, they would only loose one day's effort as a worst case scenario. However, if the system along with the on-site disk were to fail, there is the potential to lose up to one weeks worth of work. It is therefore imperative to think carefully about how to configure your backup cycles to ensure that the amount of work that might be lost
Whatever your decision on retaining backups, it is helpful to try out the route and make sure that you can recover your data. To avoid disrupting your existing machine, you may prefer to try recovery on a virtual machine using Microsoft Virtual PC or Oracle VirtualBox.
Many organizations store their backups off-site at a local bank or at a different site. Some pay to upload backups to the cloud. Wherever you decide to keep your backups, try to choose a place where the same kinds of disaster, for example flood or fire, would not affect both the system and the backup. You also need to consider how secure your backup is where it is stored.
If after considering all these options you find yourself confused, you should balance the cost of downtime against that of seeking professional advice now rather than later when your strategy has already failed.