Raid 1 - Accusys ACS-8990 User Manual

RAID 1

RAID 1 is commonly referred to as Disk Mirroring, Disk Shadowing or Disk Duplexing as all data
is duplicated across all disks. As data is identical on all disks, storage capacity is that of the
smaller disk. RAID 1 has poor performance for write operations but very high performance for
read intensive operations.
RAID 1: Mirroring
Characteristics:
Better Read transaction rate then single disks,
same Write transaction rate as single disks.
100% redundancy of data means no rebuild of
data is necessary in case of disk failure, just a
copy to the replacement disk.
All the disks have the same data.
Raid level 1 requires at least two drives.
Storage capacity = Capacity of smallest disk
80
Arrangement of data blocks saved on a Level 1 array
ACS-8990/89200/89230 User's Manual
Recommended use:
Accounting
Payroll
Financial
Any application
requiring high
availability