SAS2 Integrated RAID Solution User Guide | Chapter 2: Overview of Integrated RAID Mirrored Volumes Mirrored Volume Features |
2.4 Mirrored Volume Features
2.4.1Resynchronization with Concurrent Host I/O Operation
2.4.2Hot Swapping
2.4.3 Hot Spare Disk
2.4.4 Online Capacity Expansion
2.4.5 Media Verification
This section describes features of Integrated Mirroring, Integrated Mirroring + Striping, and Integrated Mirroring Enhanced volumes. You can configure one or two mirrored volumes on each LSI SAS2 controller.
The Integrated RAID firmware allows host I/O transactions to continue on a mirrored volume while it resynchronizes the volume in the background. The firmware automatically starts resynchronizing data after a disk failure activates a hot spare, or after a disk in a mirrored volume has been hot swapped.
The Integrated RAID firmware supports hot swapping, and it automatically resynchronizes the
Following a
You can configure two disks as global hot spare disks to protect data on the mirrored volumes configured on the SAS2 controller. If the Integrated RAID firmware fails one of the mirrored disks, it automatically replaces the failed disk with a hot spare disk and then resynchronizes the mirrored data. The firmware automatically receives a notification when a hot spare replaces the failed disk, and it then designates that disk as the new hot spare.
The OCE feature enables you to expand the capacity of an existing
NOTE: The new drives must have at least 50 GB more capacity than the original drives of the volume.
After you replace the disk drives and run the OCE command, you must use a commercial tool specific to the operating system to move or increase the size of the partition on the volume.
The Integrated RAID firmware supports a background media verification feature that runs at regular intervals when the mirrored volume is in the Optimal state. If the verification command fails for any reason, the firmware reads the other disk’s data for this segment and writes it to the failing disk in an attempt to refresh the data. The firmware periodically writes the current media verification logical block address to nonvolatile memory so that the media verification can continue from where it stopped prior to a power cycle.
LSI Corporation Confidential August 2010 | Page 11 |