DELL H200 Manuel D’Utilisation
16
Overview
Figure 2-2.
Example of RAID 0
RAID 1
With RAID 1, data written to one disk is simultaneously written to another
disk. If one disk fails, the contents of the other disk can be used to run the
system and rebuild the failed physical disk. The primary advantage of RAID 1
is that it provides 100 percent data redundancy. Because the contents of the
disk are completely written to a second disk, the system can sustain the failure
of one disk. Both disks contain the same data at all times. Either physical disk
can act as the operational physical disk.
disk. If one disk fails, the contents of the other disk can be used to run the
system and rebuild the failed physical disk. The primary advantage of RAID 1
is that it provides 100 percent data redundancy. Because the contents of the
disk are completely written to a second disk, the system can sustain the failure
of one disk. Both disks contain the same data at all times. Either physical disk
can act as the operational physical disk.
NOTE:
Mirrored physical disks improve read performance by read load balance.
Figure 2-3.
Example of RAID 1
stripe element 1
stripe element 5
stripe element 9
stripe element 5
stripe element 9
stripe element 2
stripe element 6
stripe element 6
stripe element 10
stripe element 3
stripe element 7
stripe element 7
stripe element 11
stripe element 4
stripe element 8
stripe element 8
stripe element 12
stripe element 1
stripe element 2
stripe element 3
stripe element 2
stripe element 3
stripe element 1 duplicated
stripe element 2 duplicated
stripe element 3 duplicated
stripe element 2 duplicated
stripe element 3 duplicated
stripe element 4
stripe element 4 duplicated
PERC H200.book Page 16 Tuesday, July 13, 2010 4:15 PM