Redundant Array of Independent Disks refers to next-level storage technology. RAID replaces the single drive in your server and substitutes it with a minimum of 2 to 4 disks which is contingent on the RAID level you decide to install.
RAID provides efficiency, backup, and scalability in a system. The type of RAID you ultimately install establishes the advantages and disadvantages deriving from your system. Therefore, you need to determine what you require from a RAID system prior to installing one. The type of RAID also dictates the type of recovery you’ll require if one of the drives crash.
Below is a list of prevalent RAID types and their associated advantages and disadvantages:
RAID 0: Efficient, But Lacks Recovery Choices
RAID 0 grabs your data, writing it across various drives. This is referred to striping. Preferably, each individual drive is on its own controller. The advantage is that you receive high performance write transactions for the system. Unfortunately, the major disadvantage is that if one drive crashes, all of your precious data is gone with the exception of utilizing a backup solution. Nonetheless, RAID 0 is fantastic if you are able to create data backups which mean you don’t have to fret about data loss. RAID 0 shouldn’t be deployed for critical systems since failure is a possibility.
RAID 1: Backups, But Lack Performance
RAID 1 integrates mirroring. Mirroring indicates that for each transaction written to the hard drive, another copy of it is written to another drive. Hence, the advantage is that you possess a complete backup of all data.
The disadvantage is that data has to be written twice, taking a longer time. This entails that performance will suffer. You shouldn’t employ RAID 1 in a system that depends on performance. Another disadvantage is that your total storage capacity is split in half. If you possess a 2TB drive, the actual storage capacity is 1TB.
If one drive fails, the mirrored driver may take over. But remember that replacing the failed driver is essential since if the second drive fails, your data is gone.
RAID 5: Striping Accompanied By Data Recovery
RAID 5 amalgamates the striping from RAID 0 with parity. Parity supplies the drives with the capability to reconstruct your data in case one drive fails. With RAID 0 and 1, you run into trouble if a drive crashes. Mirroring can be perceived as insufficient if you don’t replace the crashed disk.
When using RAID 5, data is dispersed across various drives as well as parity data. This illustrates that when one drive fails, you have to install a replacement which would mean that the data is reconstructed. It may take time to reconstruct data, but it’s better than losing it completely. Keep in mind that you require three disks for RAID 5.
RAID 6: Two Disks For Parity
Similar to RAID 5, parity is written to disks to recover data if one disk fails. The dissimilarity between these two RAID levels is that RAID 5 utilizes a single disk for parity and RAID 6 utilizes two disks. This is advantageous since more than one disk can fail in your array. You require a minimum of four disks to deploy RAID 6.
RAID 10 – Amalgamation of RAID 0 and RAID 1
You may create a hybrid array that employs both RAID 0 and RAID 1 solutions. It grants you the advantages of speed and redundancy. Keep in mind that half of the storage will be used for mirroring. Thus, the disadvantage is requiring more storage capacity. Because of the concerning use of disk space, most admins prefer to implement RAID 5 or RAID 6 instead.
RAID 2, 3, and 7 aren’t as prevalent among admins. If you intend to deploy RAID, you ought to distribute the drives on different controllers for utmost security. Remember that despite having many drives, if your controller crashes and all of your drives are on it, your storage is gone.