—I/0 setting: Determines whether to read/write from cache to improve performance:
^Cache I/O: Writes to the cache and next read checks the cache first.
^Direct I/O: Never uses cache, all data goes from host to disk to host.
•Redundancy through:
—Configuration stored in nonvolatile RAM and on the drives (COD).
—Hot swap support.
—Optional battery backup for cache memory. Controller provides fast or trickle charges.
SAS and SATA Features
•Provides eight independent phys, each supporting 3.0 Gbps and 1.5 Gbps SAS and SATA data transfers.
•Scalable interface that supports up to 15 SATA devices, 40 logical devices, or 32 SAS devices via expanders.
•Transfers data using SCSI information units.
•Supports SSP to enable communication with other SAS devices.
•Supports SMP to communicate topology management information.
•Supports single PHY or wide ports consisting of 2, 3, or 4 PHY within a single quad port.
•Allows addressing of multiple SATA targets through an expander if using SATA 2.0- compliant hard disk drives.
•Allows multiple initiators to address a single target (in a
Online Capacity Expansion and RAID Level Migration Rules
•Migration must occur to the same or larger capacity configuration.
•Migration cannot occur if there is more than one virtual disk in a logical array.
•Migration and OCE cannot be done on Spanned Arrays (RAID 10, 50).
•Migrations supported are: RAID 1 to RAID 0, RAID 5 to RAID 0.
•With OCE, migrations supported are RAID 0 to RAID 1, RAID 0 to RAID 5, RAID 1 to RAID 5.
Intel® RAID Controller SRCSAS144E Hardware Guide | 4 |