A RAID is a way of storing data across multiple drives (HDDs/SSDs). This is done to protect the data in the case of a drive(s) failure. By using multiple disks, you increase the mean time between failures and back up redundancy by mirroring identical data onto more than one drive. Another method is striping data, which helps spread the data over multiple disk drives.
Hardware RAID vs Software RAID
Hardware RAID: In hardware RAID, a dedicated RAID controller is used. This controller is a separate physical device, typically in the form of a PCIe card, that is responsible for managing the RAID array. It has its own processor, cache, and firmware to handle RAID operations independently of the host system's CPU. The RAID controller is able to manage disks independently from the computer without using processing power. This allows for faster data access and easier replacement of downed disks by replacing the device.
Software RAID is a type of RAID managed by software in the operating system. The disk controller software is embedded in the computer system that is compatible with the operating system. The disks are managed as part of the associated computer and may also be used by multiple devices while being applied in one operating system. host system's CPU and operating system to handle RAID functions. It relies on software drivers or RAID management utilities provided by the operating system to create, manage, and monitor the RAID arrays.
Should you use hardware RAID or software RAID?
Hardware RAID is better able to handle high performance situations with flexibility, while software RAID has to share the operating system processing, limiting its performance. Based on the controller software or drives, the software RAID can have access speeds faster than the hardware RAID, while hardware RAID speeds are dependent on the controller and types of drives. Generally, hardware RAID costs more than software RAID, but it is able to provide better performance without OS limitations.
- Since hardware RAID has a dedicated controller with its own processing power and cache, it generally offers better performance and reliability.
- Hardware RAID typically requires an additional investment in RAID controller cards, which can increase the overall cost of the storage solution.
- Hardware RAID controllers support a wide range of RAID levels (e.g., RAID 0, RAID 1, RAID 5, RAID 6, RAID 10) and offer more flexibility in terms of configuring and changing RAID settings.
- Since the RAID configuration is stored on the RAID controller.
- If you move the drives and the RAID controller to another compatible system, the RAID configuration remains intact.
- Software RAID removes the need for a RAID controller so generally they are cheaper than hardware RAID systems.
- Software RAID may introduce some overhead, particularly when dealing with complex RAID configurations or under heavy loads.
- Software RAID configurations are tied to the specific host system and its software setup.
- Moving software RAID arrays to a different system might require reconfiguration or additional drivers.
In summary, hardware RAID generally offers better performance and more RAID configuration options but comes with higher upfront costs. Software RAID is more cost-effective but may have slightly lower performance and flexibility depending on the host system's resources. The choice between hardware and software RAID depends on factors such as budget, performance requirements, and level of configurability needed for a particular storage solution. If you have the need for performance and reliability, Hardware RAID is more suitable for your needs.