RAID 5 data recovery is concerned with restoring data that was lost from a failed RAID 5 storage system.
RAID is an acronym for redundant arrays of independent disks / redundant arrays of inexpensive disks. Despite the second interpretation of the RAID acronym, if you want to decrease the probability that you require RAID data recovery, the Data Savers team strongly encourages you to use quality hard drives in your RAID appliance. RAID 5 is one of the most popular RAID configurations, and after reading this article you will understand why so many businesses and consumers utilize RAID 5.
What is RAID 5?
RAID 5 configurations utilize three hard drives at minimum. While it is theoretically possible to have an unlimited number of hard drives in your RAID 5 setup, operating at least three drives is essential. Irrespective of how many drives are in your configuration, the system will function as if you have a single logical storage unit. While it may appear to the end user as a single logical drive, RAID 5 offers significant advantages in read speed and reliability.
When data is saved to a RAID 5 system, processes known as striping and parity are responsible for organizing that data in a specific arrangement across the entire array. The definitions in the following section should provide additional insight into both of these concepts. Visit this article by Western Digital to learn more about different RAID configurations.
What is Striping?
Hard drives are made up of a limited number of addressable blocks known as strips. When RAID systems separate these strips across three or more connected hard drives it is known as a stripe. RAID 0 is a system that only utilizes striping. Exclusively utilizing striping does not offer the benefit of fault tolerance for drive failure, which is why RAID 0 is rarely used in situations concerning mission critical data. While striping does not improve reliability, it does significantly increase performance with read / write operations.
What is Parity?
Parity is the concept that is responsible for RAID 5’s tolerance to single-drive-failure. Maintaining duplicate copies of each drive is a limiting factor for many RAID users as it dramatically increases costs by requiring twice as many hard drives to offer the same storage as a RAID 0 system would (with those same drives). Parity is the answer to this quandary, because it enables protection of all data in the storage system through the use of parity bits that can be used to recreate the data from the rest of the system. A RAID 4 configuration stores parity information on a separate drive. Having one drive that stores parity data creates a single point of failure, and RAID 4 is rarely used for this reason. RAID 5 utilizes distributed parity information, so the array is capable of restoring each drive given every other drive remains operational.
Fault Tolerance in RAID 5 Storage
The failure of a single hard drive is detrimental to users who are relying on one internal or external hard drive for storage of important data. If a single drive from a RAID 5 system fails, the array is capable of recreating the exact same data structures on a replacement drive. Not only that, but an end-level user utilizing information from a RAID 5 system would be completely ignorant to hard drive failure of one hard drive. While it may appear that the data in RAID 5 is well protected by this fault-tolerance, the prospect of losing multiple hard drives in a short time span is far more likely than you may have thought.
Multiple Hard Drive Failure and RAID 5 Data Recovery
Many RAID users purchase a single make and model of hard drive when they are first setting up their storage appliance. In these scenarios, it is within the realm of possibility that these hard drives are virtually identical, as they came off the assembly line within minutes of one another. These (practically) identical hard drives receive a read / write workload that is also virtually identical. Is it difficult to imagine more than one drive failing in a situation like this?
If this section describes your RAID 5 data loss scenario all hope is not lost. Reach out to Data Savers ASAP, and an experienced data recovery professional will provide you with a more detailed assessment based on the specifics of your situation.
RAID 5 Data Recovery
The previous example illustrates how it is entirely possible for multiple hard drives to fail in a short span of time. This phenomenon is responsible for a vast majority of the RAID 5 data recovery cases we have seen in the Data Savers lab. Fortunately, these individuals who were impacted by RAID 5 failure had the good sense to bring their storage appliance to Data Savers. The experienced data recovery engineers at Data Savers are professionals at RAID data recovery. If you or your business has encountered data loss due to RAID 5 failure, reach out to the Atlanta data recovery professionals at Data Savers!