A Degraded RAID is when one or more redundancy disks have stopped working. Depending on the Array type this will result in performance loss. The safest way to know if RAID is degraded is to access the controller’s management software. On IBM/Lenovo servers this software is called MegaRAID Storage Manager. Another way to visualise is also to observe if there is any orange LED lit on the disks belonging to the array in question.