When planning a backup strategy , there are five things that you should consider
1) Decide what data needs to be backed up
This includes knowing where the data is located and what type of data it is. Some data will be larger than others and may need a different backup solution for more minor data. For example, video files are generally huge compared to text-only documents. Documents can easily be backed up in almost real-time to the cloud, whereas video files could take many hours to upload, and a backup to a local disk may be more viable.
2) Make sure the data is backed up
A backup is only as good as the last time you tested restoring the data. Disks sometimes fail, particularly as they age. If this happens and backups stored on the disk are useless. Likewise, backing up to the cloud is only helpful if the login details are known. If the login details are lost, or the download speed is slow, the backup may not be beneficial.
Backups should be tested in three ways.
a) check the data has been written to the backup device - often, backup software will provide this check automatically
b) check the data is valid - restore a few files and ensure they are being opened and contain the information you expected, and the file is not corrupt
c) complete restore - Restore all of the data and check that it can be used. This is particularly needed for system backups to ensure the restored system can boot and function properly.
3) Make sure backups are stored in multiple locations - '3-2-1' backups
a) have three copies of your data
b) use two different media, e.g. tape and disk, disk and cloud
c) one offsite copy
4) Set recovery point objective
Understand how much data you are willing to lose, define how often you need to backup and how you back up the data so the backup completes before the next one starts.
5) Know recovery time objective
How long will it take to restore the data and prioritise the order in which data is refreshed?
For example, a cloud backup will typically take longer to restore than data backups on a local disk.