Explain the RAID concept with an example.

Question

Accepted Answer

RAID stands for Redundant Array of Independent Disks. It is a technology used to combine multiple hard drives into a single unit for data protection and performance improvement.

RAID 0: Striping without parity, offers increased performance but no data protection
RAID 1: Mirroring, duplicates data across multiple drives for data redundancy
RAID 5: Striping with distributed parity, balances performance and data protection
RAID 10: Combination of RAID 1 and RAID 0, offers both performance and redundancy

Accepted Answer

When it comes to server disk capacity optimization or data security, the sure solution for any organization is RAID.

RAID is an acronym for the term “Redundant Array of Inexpensive (or “Independent”) Disks.” In a RAID set up, the data of an organization is copied into multiple disks, thus creating a fail-proof system where data is better optimized, and data loss is prevented. A RAID system usually involves the use of two or more disks.

BASIC WAYS OF RUNNING RAID

There are basically two ways of running RAID: the software RAID and the hardware RAID.

The hardware RAID works with a special controller. All the disks are connected to this singular controller. The RAID calculations are carried out by an onboard processor, reducing the workload on the CPU of the host system. Today’s CPUs are efficient enough to carry the extra load of the varying disks and eliminating the place of the onboard processor which is now seen by many as an obsolete method.

The software raid, on the other hand, is part and parcel of the server OS. It is cost-effective and easy to implement and maintain. It doesn’t need any additional hardware(s) (which are usually expensive) to run. All modern Unix-like operating systems and Windows operating systems support software RAID.

VARIOUS RAID LEVELS; THEIR ADVANTAGES AND DISADVANTAGES

When it comes to choosing a RAID type, there are many options that you can select from. But how do you know the RAID type that is suitable for you?

Below is a rundown of raid types, their features, requirements, advantages, disadvantages, as well as GTHost special recommendations.

RAID 0

The RAID 0 is also known as disk stripping.

Features

In RAID 0, the data is actually split between two or more disks. Some people do not even consider it as a RAID type. This is because data is not actually stored into all disks but split among the different disks. The resulting consequence is that the work the computer does is handled by multiple disks instead of one.

Requirements

can run on software or hardware platforms;
needs at least 2 disks to run;

Advantages

Speed in performance is the advantage of RAID 0. Read and write actions are performed at a much faster rate. Since multiple disks are responsible for the job of one disk.
Less space is needed for striping.

Disadvantages

In striping, the data is not duplicated to multiple discs, but actually stripped or spread across. The consequence of this is that there is little or no fault tolerance. This means that there is a very high possibility of data loss. If anything were to happen to any of the disks, all the data would be lost.

GTHost Recommendation

If your work relies more on performance speed e.g. live streaming, POV, VOD Edge Server, etc., then you should consider using the RAID 0.

RAID 1

RAID 1 is also known as data mirroring

Features

In RAID, the data is duplicated into two or more drives. This mirroring effect makes for safe data storage.

Requirements

works with hardware or software platforms;
needs at least two disks in server to run;

Advantages

In mirroring, there is redundancy. This means that data loss is less likely in this type of RAID, especially since data is duplicated. Hence, the loss of one disk is not a loss of data.
Read operations can be carried out at a faster speed

Disadvantages

Writing speed performance is slow.
For redundancy sake, more space is consumed in keeping similar data.

GTHost Recommendation

If your business is more data reliant, then the RAID 1 is a valid option to hold unto.

RAID 5

This RAID type works through stripping by parity.

Features

This RAID type uses stripping just like RAID 0 but with the added advantage of parity. While data is spread across all disks, a little bit of space (one third) of each disk is used to save parity information: a small amount of data that can be used to describe and recreate a larger amount. So if a disk crashes, it can be replaced easily using the parity information.

This can be done without disrupting the functionality of the server or NAS.

Requirements

a minimum of three disks are required to run the RAID 5;

Advantages

Better read and write speed performance.
Reduced cost for redundancy.
The server functions even when a disk fails.
Allows for disk swap in case of a disk crash or failure.

Disadvantages

Can’t handle more than a single disk failure.
Lagging performance for servers with a high write operation.

GTHost Recommendations

RAID 5 has performance, speed, and redundancy. This makes it an option for anyone who wants to achieve speed and data security on the go. It would prove very useful for file storage servers and application servers.

RAID 6

RAID 6 is similar to RAID 5 except that the former offers double parity.

Features

The RAID 6 stores an extra parity block that offers more data security and reliability. With this, you can have two disks down and still have your server running.

Requirements

a minimum of four discs are required to run RAID 6;

Advantages

Better data security and redundancy. It can work in spite of two disk failures.
Increase in reading performance.

Disadvantages

Low performance in servers with a ton of write operations.

GTHost Recommendations

With better performance and security, RAID 6 is a good choice for large file storage servers and application servers.

RAID 10

RAID 10 is the combination of RAIDs 1 and 0(RAID 1+0). The resultant is the hybrid of stripping and mirroring.

Features

This hybrid has the redundancy of RAID 1, and the increased performance of RAID 0, making it a more effective option.

Requirements

a minimum of four disks are required to run the RAID 10;
can run on both software and hardware platforms. However, using the software platform may mitigate the benefits of RAID 10.

Advantages

The optimal performance level guaranteed.
Great redundancy and fault tolerance.

Disadvantages

Data mirroring increases the cost of memory.

GTHost Recommendation

With the best of both worlds in security and performance, the RAID 10 is the best pick if you require optimal security and performance.

Accepted Answer

There are many types of servers, including web servers, mail servers, and virtual servers.

Accepted Answer

There are many types of servers, including web servers, mail servers, and virtual servers.

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Explain the RAID concept with an example.

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