Intel SRCU31 5.1.3.5Array Roaming, 5.1.4.1Global Hot Spare, 5.1.4.2Hot Plug Disk Drive Support

RAID Features

5.1.3.5Array Roaming

Array Roaming allows the user the ability to move a complete array to another system (with drives in any SCSI ID slot) and still preserve RAID configuration and user data on that array. SRCU31 firmware versions do not have to be the same on both systems (firmware updates are backwards compatible). The array being moved must be connected to the destination server while it is offline.

Summary

•New physical disks can be added without rebooting.

•RAID volumes are re-allocated across arrays, maintaining capacity.

•Available array capacity increases by the size of the added disk(s).

•RAID volumes presented to the operating system do not increase in capacity.

Additional capacity may be made available to the OS by adding a new volume(s) on the newly created free space on the array.

5.1.4High Availability/Redundancy

5.1.4.1Global Hot Spare

The global hot spare is one of the most important features that SRCU31 provides to deliver a high degree of fault-tolerance. A global hot spare is a spare physical disk drive that has been marked as a global hot spare and therefore is not passed through to the host OS and is not a member of an array. If a disk drive used in a RAID volume fails, then the global hot spare will automatically take its place and the data previously located on the failed drive is reconstructed on the global hot spare.

For this feature to work properly, the global hot spare must have at least the same capacity as the drive it replaces. Global hot spares only work with RAID 1 and RAID 5 volumes. You may configure up to 4 global hot spares with SRCU31. Global hot spares count toward the maximum number of disks that are supported by SRCU31.

During the automatic rebuild process, system activity will continue as normal, however, there may be a slight degradation in performance as the data on the global hot spare is rebuilt.

To effectively use the global hot spare feature, you must always maintain at least one drive that is marked as a global hot spare.

5.1.4.2Hot Plug Disk Drive Support

SRCU31 supports the replacement of failed hard disk drives without having to shut down the system. However, your RAID storage backplane must support hot plug disk drives for this feature to be active.

Warning: Never remove a drive or insert a disk drive into your system while the power is on without confirming with both the disk drive and drive enclosure documentation that both the drive and enclosure are capable of supporting this action. Removing or inserting a new drive not designed for ‘hot swap’ may result in damage to your hardware and data. Even when both drive and enclosure support ‘hot swap’ it is strongly recommended that ‘hot swapping’ not be done while the drives are being accessed (active I/O). LVD drives and enclosures are especially susceptible to electrical

5-4 Intel® Server RAID Controller U3-1 User’s Manual Rev 1.0