Dell EMC Server Administrator Storage Management 9.1

RAID level 1 (mirroring)

RAID 1 is the simplest form of maintaining redundant data. In RAID 1, data is mirrored or duplicated on one or more physical disks. If a physical disk fails, data can be rebuilt using the data from the other side of the mirror.

Mirroring
Disks

RAID 1 characteristics:

  • Groups n + n disks as one virtual disk with the capacity of n disks. The controllers currently supported by Storage Management allow the selection of two disks when creating a RAID 1. Because these disks are mirrored, the total storage capacity is equal to one disk.
  • Data is replicated on both the disks.
  • When a disk fails, the virtual disk still works. The data is read from the mirror of the failed disk.
  • Better read performance, but slightly slower write performance.
  • Redundancy for protection of data.
  • RAID 1 is more expensive in terms of disk space since twice the number of disks are used than required to store the data without redundancy.