RAID Tips 7 of 10 - Test your RAID
The fault tolerance needs to be tested so that you
- know exactly how the RAID behaves when a hard drive fails;
- ensure that the RAID is actually capable of surviving a disk failure.
When deploying a fault-tolerant array (RAID 1, RAID 5, or RAID 6), test the system with a simulated disk failure.
- If you have hot swappable drive bays, just pick a random one and pull the hard drive on a live system.
- If there is no hot swap available, then disconnect one of the disks with the system powered off.
Obviously, you better do the testing before the array is loaded with the production data, or you'd have an unplanned RAID recovery incident.