RAID(Redundant Array of Inexpensive Disk or Redundant Array of Independent Disk) is a way of storing the data in different places on multiple hard disks.
Purpose of RAID
It is used to increase the logical capacity of storage devices,to improve read / write performance and ensure redundancy in case of a hard disk failure.
Advantages of RAID
- To increase the Reliability and performance of the system
- Improved redundancy in the case of a failure in some RAID configurations.
Disadvantages of RAID
- Large number of hard disks,leading to an increased failure rate.
- Greater difficulty in performing backups and system rescue or restore in the case of a failure.
The Data will be stored in alternate hard disk. striping, max capacity, max performance, no fault tolerance,
* Need Minimum 2 hard disk or partition
Data writing and reading speed is very high.
Even single hard disk fails ,we cant able to recover the data
The Data will be available in both hard disk. mirroring, least capacity, moderate performance, best fault tolerance.
* Need Minimum 2 hard disk or partition.
If single hard disk fails ,we recover the data easily.
Dis adv :
Data writing and reading speed is very low ,when comparing to RAID 0.
The data will be available in all hard disks. Single parity, good capacity, good performance, single drive failure tolerance,
* Need Minimum 3 hard disk or partition.
* Even a single hard disk crashes ,we can recover data using two hard disks.
* Writing and reading speed is very high comparing RAID-0 and RAID-1
Dis Adv :
* If two hard disk fails ,we cant able to recover the data.
* Cost is very high.