Upon identifying a potential cause of an issue with a RAID 5 array, especially when the array is making clicking noises that suggest a failing drive, the next critical step is to perform a full data backup. This ensures that data is preserved before any further troubleshooting steps are taken, such as replacing the failing drive.
RAID 5 provides fault tolerance, but ensuring data is backed up minimizes the risk of data loss during the repair process.
References:
* CompTIA A+ Core 1 (220-1101) Exam Objectives, especially the sections dealing with storage devices and data backup and recovery principles, which would include strategies for dealing with potential drive failures in RAID arrays.
* Best practices in data management and protection, emphasizing the importance of securing a backup before undertaking hardware replacements or repairs in storage arrays to prevent data loss.