Tandberg Data BAKSTOR, Руководство администратора

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Tandberg Data
BakStor User Manual 25
4 Advanced Configuration
4.1 Choosing a RAID Level
The BakStor is a disk based product which uses today’s industry approved disk management
(RAID).
The advantages of choosing RAID are: Availability, Capacity and Performance. Choosing the
right RAID level and drive failure management will give the right balance between Availability,
Performance and Capacity.
Before the BakStor can allow disk availability to the user a RAID or logical drive must be
created.
There are various levels of RAID that available with the BakStor:
RAID-0 Disk striping
RAID-1 Disk Mirroring
RAID-1 + hot spare Disk Mirroring with dedicated ‘hot spare’ disk drive.
RAID-5 Multiple Block Striping with Interspersed Parity
RAID-5 + hot spare Multiple Block Striping with Interspersed Parity and with
Dedicated ‘hot spare’ disk drive
4.1.1 RAID-0 (Disk Striping)
A RAID-0 allows multiple disks to be combined to create one large volume.
Performance is greatly improved since all the disks are accessed in parallel and is considered to
be the fastest way to access multiple disks drives.
A RAID-0 offers no protection against disk failure. If a single disk in the RAID-0 set should
fail, the entire RAID set will fail.
If your environment depends on quick data access and less on protecting against disk drive
failure RAID-0 would be the best option.
Example:
In the BakStor there are 4 x 250GB capacity disk drives. By creating a RAID-0 one single
logical drive with a size of 1000GB will be available instead of four single 250GB drives.
(4 x 250GB =1000GB usable)
Often RAID-0 is used for non-critical data that may only be an archive or second copy of data
that is not accessed regularly and may be held for a short period.
2 TB limit
Note that the current version of the BakStor is not able to create a RAID larger than 2TB.
Depending on the capacity of the disks in the BakStor this may mean that not all the disks can