AMCC 3WARE 720-0138-00 - Manual (Page 51)

Naming a Unit
www.3ware.com 43
If you need to add a drive to be used as the hot spare, follow the instructions
under “Adding a Drive” on page 58.
To specify a hot spare
1 In 3DM, choose Management > Maintenance.
2 In the Available Drives list, select the drive you want as a hot spare by
marking the checkbox in front of it’s Port number.
3 Click Create Unit .
4 In the dialog box that appears, select the configuration type Spare .
5 Click Ok .
You will see the spare appear at the top of the page, under Unit
Maintenance .
Naming a Unit
Units can be given unique names to more easily identify them. A unit can be
assigned a name when it is created. It can also be named or renamed at a later
time.
To name or rename a unit through 3DM
1 Make sure the appropriate controller is selected in the drop-down list at
the right of the menu bar.
2 Choose Management > Controller Settings from the menu bar in 3DM.
3 In the Unit Names section of the Controller Settings page, locate the unit
for which you want to change the name.
Note: 3ware’s 9000 series RAID controllers use drive coercion so that drives from
differing manufacturers and with slightly different capacities are more likely to be
able to be used as spares for each other. Drive coercion slightly decreases the
usable capacity of a drive that is used in redundant units.
The capacity used for each drive is rounded down to the nearest GB for drives
under 45 GB (45,000,000,000 bytes), and rounded down to the nearest 5 GBytes
for drives over 45 GB. For example, a 44.3 GB drive will be rounded down to 44
GBytes, and a 123 GB drive will be rounded down to 120 GBytes.
If you have 120 GB drives from different manufacturers, chances are that the
capacity varies slightly. For example, one drive might be 122 GB, and the other 123
GB, even though both are sold and marketed as “120 GB drives.” 3ware drive
coercion uses the same capacity for both of these drives so that one could replace
the other.