Created on: November 7, 2014
Last updated: August 25, 2015
Note: this topic does not deal with data parity, mirroring or other back-up related technologies.
In most situations, when you have a failed drive in a RAID enclosure, you should remove the failed drive immediately from the RAID and replace it.
Not removing a drive from the array after it has failed can cause other problems, including corruption or failure of other disks in the array. A failed disk can also generate electrical noise over the bus regardless of the bus connection type, which can trigger additional problems. Generally speaking, regardless of RAID type, the sooner you can replace a failed drive, the better off you will be. What that process will look like depends wholly on the enclosure and RAID mode you are using and whether you are attempting to maintain data integrity. Please see your manual or user guide for more details.