FastTrak SX4300, SX8300 User Manual
46
Ranges of Disk Array Expansion
There are limitations to how large you can expand a logical drive, depending on
the size of your current logical drive.
The current SCSI and Fibre Channel HBA cards and PC Operating Systems
support a 10-byte LBA format. This means that a logical drive can have up to 4
billion address blocks or sectors.
Multiply the number of blocks by the sector size to find the capacity of a logical
drive:
4,000,000,000 blocks x 512 bytes per sector = 2,048,000,000,000 bytes
of data for a 2TB drive.
Note that you cannot change the size of the sectors nor can you increase the
number of address blocks above 4 billiion.
RAID 0 RAID 10 • • •
RAID 5 • • •
RAID 1 •
* Increases the existing redundancy
Important
• The Target logical drive may require more disk drives tha n the
Source logical drive
• If the Target logical drive requires an EVEN number of disk
drives but the Source logical drive has an ODD number, ADD
a disk drive as part of the migration process
• You cannot reduce the number of disk drives in your logical
drive, even if the Target logical drive requires fewer disk
drives than the Source logical drive
• RAID 1 (mirror) works with two disk drives only
• You cannot migrate a logical drive when it is Critical or
performing activities such as Synchronizing, Rebuilding and
PDM
• RAID level migration is not possible to or from JBOD
From To Increase RedundancyCapacity Performance Add Lose