Generally speaking RAID storage is known for its systems that provide a certain amount of redundancy and can act as a backup in case something goes wrong. However how safe is the data on RAID storage really?
The answer to that is not as simple as you may imagine, and it really depends on the type or ‘level’ of RAID that is in use. Different levels of RAID storage use very different technology that impact how safe the data that is stored will be.
Mirroring and Parity
In simple terms, all types of RAID storage apart from RAID 0 use some form of mirroring or parity. The difference between mirroring and parity is a bit subtle – mirroring involves replicating data that is stored precisely, whereas parity involves generating a parity checksum that can be used to restore any data.
While both mirroring and parity provide a form of backup and act as a safety net in case something goes wrong with a particular sector or drive – the degree to which they do so can vary. For example RAID 5 uses a single parity system that can hold up when one drive fails, but RAID 6 uses double parity that allows it to hold up even when two drives fail.