RAID 1
RAID 1 mirrors all data from one hard disk drive to a second one hard disk drive, thus providing complete data redundancy. However, the cost of data storage capacity is doubled.
This is excellent for complete data security.
RAID 5
RAID 5 offers data security and good performance. It is best suited for networks that perform many small I/O transactions at the same time, as well as applications that require data security such as office automation and online customer service. Use it also for applications with high read requests but low write requests.
RAID 5 includes disk striping at the byte level and parity information is written to several hard disk drives. If a hard disk fails the system uses parity stored on each of the other hard disks to recreate all missing information.
JBOD
Although a concatenation of disks (also called JBOD, or "Just a Bunch of Disks") is not one of the numbered RAID levels, it is a popular method for combining multiple physical disk drives into a single virtual one. As the name implies, disks are merely concatenated together, end to beginning, so they appear to be a single large disk.
As the data on JBOD is not protected, one drive failure could result total data loss.
Stripe Size
The length of the data segments being written across multiple hard disks. Data is written in stripes across the multiple hard disks of a RAID. Since multiple disks are accessed at the same time, disk striping enhances performance. The stripes can vary in size.
Disk Usage
When all 3 disks are of the same size, and used in RAID, M3800 disk usage percentage is listed below:
RAID Level | Percentage Used |
RAID 0 | 100% |
RAID 1 | 50% |
RAID 5 | 66% |
JBOD | 100% |
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