What happens if 2 disks fail in RAID 5?
If a second disk in a RAID level 5 disk array fails, you must replace the failed disks, then delete and recreate the disk array. You must then recreate the file systems on the disk array and copy data to the restored disk array from your backup media.
What happens when a disk fails in a RAID 5 array configured with a hot spare?
When a single disk in a RAID 5 disk array fails, the disk array status changes to Degraded. The disk array remains functional because the data on the failed disk can be rebuilt using parity and data on the remaining disks. If a hot-spare disk is available, the controller can rebuild the data on the disk automatically.
Can RAID 5 lose 2 drives?
Regardless of how many drives are in use, a RAID 5 array only allows for recovery in the event that just one disk at a time fails.
How does RAID 5 hot spare work?
Hot spare is a drive that acts as a stand by drive in RAID 1, RAID 5 or RAID 6 volume. It is fully functional drive that contains no data and is not used during normal operation. If a drive from the volume fails, the controller reconstructs the data from the failed drive to the hot spare drive.
Does RAID 5 require identical drives?
Do all drives have to be the same model and capacity for a RAID 5 array? The short answer is No, the drives don’t have to be exactly the same. The longer explanation is that for compatibility reasons, we usually recommend using the same model.
What is a hot spare in RAID 5?
RAID Tip 5 of 10 – Hot Spares Hot spares are a good addition to a fault-tolerant array. They greatly reduce the impact of monitoring on the array reliability. If a drive has failed in a fault-tolerant (RAID 1, RAID 10, RAID 5, or RAID 6) array, a vulnerability window opens.
Should I use RAID 6 or RAID 5 for my NAS?
Hot spares are most effective when a single hot spare drive is shared between several arrays. Consider for example an 8-bay NAS. If there is only one RAID 5 array in the NAS, then RAID 6 may be a better option than a hot spare. The hot spare drive just sits there idly; in a RAID 6 array, the same drive would be utilized to improve a read speed.
How many drives can a RAID array handle without a hotspare?
Go to Solution. 04-10-2018 09:40 AM All the raid configurations you mention are fault tolerant, they can lose 1 drive, raid 10 possibly more, without a hotspare. Hot spares just add to the safety of arrays, they will become an full functioning active member of an array should a drive fail.
Are hot spares a good addition to a fault-tolerant array?
Hot spares are a good addition to a fault-tolerant array. They greatly reduce the impact of monitoring on the array reliability. If a drive has failed in a fault-tolerant (RAID 1, RAID 10, RAID 5, or RAID 6) array, a vulnerability window opens. If another drive fails during this vulnerability window, the data is lost.