How should you rebuild this RAID array?

You’ve received a message in your error log that a drive in your RAID 1 array is faulty. What’s the best way to rebuild this RAID 1 array?

A) RAID 1 arrays are redundant, so you simply need to replace the bad drive

B) RAID 1 arrays are not redundant, so you’ll need to replace the drive and restore from a backup

C) RAID 1 arrays are redundant, but will still require restoration from backup after the drive is replaced

D) RAID 1 arrays cannot be rebuilt

E) RAID 1 arrays are like cats, and will only be rebuilt when they really want to

The answer: A) RAID 1 arrays are redundant, so you simply need to replace the bad drive

RAID 1 is a mirrored array, where data is completely duplicated across physical hard drives. If you lose a hard drive, the array is redundant and will continue to operate; usually without any loss of performance. I’ve personally identified bad hard drives in RAID 1 arrays that failed months prior, without anyone realizing there was a problem.

Rebuilding the drive array is relatively easy. If the drive array supports hot swapping, you don’t even need to power down your computer during the drive replacement. The RAID array will recognize that a new drive has been added to the array and will duplicate the existing data to recreate a complete RAID 1 mirror.

Want to know more? Watch “RAID.”

RAID arrays are common ways to provide high-throughput and redundancy for groups of hard drives. In this module, you’ll learn how the different RAID technologies can be used to build large-scale storage infrastructures. You’ll also learn the advantages and disadvantages of the different RAID technologies and how hardware and software RAID compares.