Avago Technologies MegaRAID SATA 150-4 (523) - Manual (Page 70)

3-22 BIOS Configuration Utility and MegaRAID Manager
Version 2.0 Copyright © 2003–2006 by LSI Logic Corporation. All rights reserved.
3.4.7.2 Easy Configuration
In Easy Configuration, the CU associates each hard drive with a single
logical drive. If logical drives have already been configured, the CU does
not change their configuration. Perform the following steps to create
arrays using Easy Configuration.
Step 1. Select Configure
→
Easy Configuration from the MegaRAID
CU Main menu.
The Management Menu array selection menu appears.
Step 2. Press the arrow keys to select specific physical drives.
Step 3. Press the spacebar to associate the selected physical drive
with the current array.
After you associate a physical drive with a current array, the
indicator for the drive changes from
READY to ONLIN A[array
number]-[drive number] . For example, ONLIN A2-3
indicates array 2 with disk drive 3.
Step 4. Press ENTER after you finish creating the current array.
Cache Policy Use this option to enable read buffering in cache memory. Cache Policy applies to
reads on a specific logical drive. It does not affect the Read-ahead cache. The default
setting is Direct I/O.
•
Cached I/O specifies that the controller buffers reads in cache memory.
•
Direct I/O specifies that reads and writes are not buffered in cache memory. Direct
I/O does not override the read policy settings. Data is transferred to cache and the
host concurrently. If the same data block is read again, it comes from cache memory.
Span The RAID controller supports spanning of RAID 1 and 5 arrays. You can span two or
more RAID 1 arrays into a RAID 10 array and two or more RAID 5 arrays into a RAID
50 array. The maximum number of drives that you can span is eight. For two arrays
to be spanned, they must have the same stripe width (they must contain the same
number of physical drives).
The options are:
Yes – Array spanning is enabled for the current logical drive. The logical drive can
occupy space in more than one array.
No – Array spanning is disabled for the current logical drive. The logical drive can
occupy space in only one array.
Table 3.10 Logical Drive Parameters and Descriptions (Cont.)
Parameter Description