In recent time, RAID technology has been put into service in almost every application such as desktops, servers, laptops, storage devices and in environments which requires a large number of hard disk drives. RAID stands for Redundant Array of Inexpensive Disks. It uses storage virtualization technology to improve the performance and reliability of the storage devices.
What is RAID?
RAID technology is a way to virtualize multiple physical disk drives into one or more logical units called RAID levels. The data of each file is distributed among all the disks in several ways referred to as RAID levels. The selection of the RAID levels depends on the size of the disk drives, the required level of reliability and performance.
The disks are configured so that the data is divided among disks through stripping which distributes the load, or they can be configured through data mirroring which ensures the content can be recovered. It is also possible to carry out striping and data mirroring together to gain both benefits. Earlier there were only five RAID levels like RAID 0, RAID 1, RAID 2, RAID 3 AND RAID 5 however the schemes have now evolved to suit vast applications. The drivers are configured to achieve enhanced data protection, performance, and capacity.
RAID Implementation
RAID technology can be implemented either as a hardware RAID wherein the setup is done by connecting a drives to motherboard via special hardware called RAID controller or they can also be implemented as software RAID wherein the setup is done by connecting drives directly to motherboard whose configuration is then managed by the utility software in the operating system. The type of RAID, be it dedicated hardware or software that best suits your application depends on how you want your data to be distributed across multiple drivers. In this article, we compare the two RAID implementation and assist you in choosing the best RAID setup for your application.
Hardware RAID
Hardware Raid uses special hardware called RAID controller for data recovery and backup. .Its implementation is based on RAID on-chip technology. It has its processor and cache memory to run the RAID application.
Benefits of Hardware RAID
One of the major advantages of the Hardware RAID is that it boosts system performance. Like said earlier, Hardware RAID has its dedicated RAID processor to run the RAID application. All the complex configuration is processed by a dedicated processor. Thus it boosts system performance by putting less strain on the main computer processor while distributing contents on the drives and restoring the backup data.
- Hardware RAID uses its DRAM cache memory for backup and restoration. This translates to better performance while writing data backups and meanwhile has less downtime for restoration.
- Hardware RAID adds more configuration options like the hybrid configuration which provides better tolerance towards one or more drive failure.
- Hardware RAID has inbuilt battery backup units and onboard flash memory on RAID cards. This prevents data corruption during loss of power.
- Hardware is compatible with different operating systems and it can be accessed from any system.
Drawbacks of hardware RAID
- The cost of Hardware RAID is more because the setup requires more hardware.
- Hardware RAID doesn’t provide better performance for certain setups that use Flash storage arrays(SSD).
Software RAID
Unlike the Hardware RAID, the RAID Software doesn’t use any special hardware to connect the storage devices. Here the storage devices are directly connected to the host computer. The distribution of content across the drives is managed solely by the utility Software in the Host operating system.
Benefits of Software RAID
- Most of the major operating systems like Microsoft, Apple and Linux support Software RAID configuration.
- Unlike Hardware RAID, the software RAID setup is not expensive as you don’t need any dedicated hardware for the RAID setup. The RAID configuration is done within the operating system itself.
- Software RAID is mostly suitable for simple RAID 0,1,10 processing which doesn’t cause too much load on the system
Drawbacks of Software RAID
- Software RAID can affect the overall system performance while performing complex RAID configuration. Software RAID implementation is not suitable if there are too many drivers.
- Only limited RAID levels are supported by the operating system and there is little scope for operating system migration.
- RAID is more vulnerable to viruses and other security attacks as it is running inside the host computer system.
- The server-side problem can impact data integrity due to system crashes.
Software RAID vs Hardware RAID – Which is better?
The type of RAID that best suits the performance and data availability varies from application to application. Software RAID is mostly suitable for the entry-level RAID 0,1,10 processing which doesn’t cause too much load on the system. However, they cannot be used as a high-performance solution.
Hardware RAID is mostly used by the application to scale up the availability and performance whereas Software RAID is mostly suited for the workstation with limited data storage requirements and entry-level servers which do not require boot protection.
That being said, Hardware RAID is used in work stations that require large data storage and excel in the performance. Since the Hardware RAID uses a dedicated controller, it is more suitable for applications that require complex RAID configurations and don’t impose a heavy load on the system resources like the Software RAID.
In summary, Hardware RAID is an attractive option for all the entry-level servers to enterprise-level servers to have the highest availability and performance solution. However, Software RAID is an attractive option if you are trying to save some money on the initial investment.