RAID 5 has earned a lot of kudos thanks to its high speed and fault tolerance. But it does not mean that it won’t fail. This article will introduce the 3 common ways that RAID 5 systems can fail and lose data as well as the necessary solutions.
RAID 5 is preferred by most common users. It must consist of at least 3 drives. Owing to its distributed parity, data redundancy can be realized perfectly. That is to say, if one drive fails, the RAID controller will be able to rebuild the array and enable the array to continuing operating.
However, many people have a misconception about the data redundancy in the RAID 5 system. They consider it as a substitute of backup solutions. As a matter of fact, redundancy is completely unequal to backup. RAID 5 isn’t error proof. It can suffer failures as well. Therefore, we should keep backing up our critical data to avoid any kinds of data losses, like PST email corruption. Now we’ll introduce RAID 5 failures in detail.
1. More Than One Drives Fail Simultaneously
As mentioned above, RAID 5 can tolerate one drive failure. But it’s only limited to one drive. Provided that one more drive fails, the whole array will be damaged and go on strike thoroughly. It will render the array unreadable. When a drive fails, the RAID 5 will begin to rebuild. In the rebuilding procedure, the remaining disks will be subjected to tremendous pressures. Therefore, various mechanical issues can occur, such as the drive head crash and the spindle motor damages, etc. So the other drives may become prone to corruption.
Solutions: It is suggested that you should immediately replace the corrupt drive as soon as it fails. Otherwise, more hard drives will be corrupt subsequently. Also, getting hold of additional backups is more than a matter of necessity.
2. RAID Controller Issues
RAID controller is responsible for managing all the drives in the array. As you can imagine, if something wrong happens to the controller, how severe the outcome would be. It will lead to terrible parity loss. Sometimes, you might only notice the slow performance but still can access your data. But at times, the array can stop working directly. The impacts just depend on the extent of controller damages. In addition, controller issues can disable the RAID 5 system’s rebuilding feature.
Solutions: It is much more ccomplex and difficult to dispose of the controller issues. Thus you had better contact related professionals in time.
3. RAID 5 Failures in Rebuilds
RAID 5 systems are considerably weak and sensitive in the rebuilds. Hence, once some terrible events, like power outages, take place suddenly in this course, the entire arrays will be destroyed. The RAID 5 will lose its vitally significant parity information. In the end, rebuilding the array successfully will become impossible.
Solutions: In this case, don’t try to rebuilding the array once again. Just power off the entire RAID 5 systems and resort to RAID recovery experts.
Shirley Zhang is a data recovery expert in DataNumen, Inc., which is the world leader in data recovery technologies, including repair SQL file error and outlook repair software products. For more information visit www.datanumen.com