Removal and Replacement Procedures

Hot-Plug SCSI Hard Drive

CAUTION: If you must replace a hot-plug drive, follow the guidelines in this section. Failure to do so can result in data loss and can void the warranty.

RAID 0 is not a fault-tolerant configuration. Never remove a drive from a RAID 0 array unless it has failed. Drive failure is indicated by an amber drive failure LED. In a RAID 0 configuration, removal of an operating drive results in data loss. To remove a drive without losing data, always back up the entire array, replace the drive, and restore the entire array. Backing up a single drive and replacing it does not restore the array.

Some instances exist in which you may replace a drive in RAID 1, 5, and Advanced Data Guarding configurations. To determine when drive replacement is possible without data loss, use the hot-plug SCSI hard drive LEDs combination table in Chapter 4, “Component Identification.”

Follow these additional guidelines when replacing drives:

•Never remove more than one drive at a time (or two drives if you are using Advanced Data Guarding). When you replace a drive, the controller uses data from the other drives in the array to reconstruct data on the replacement drive. If you remove more than one drive, a complete data set is not available to reconstruct data on the replacement drive(s) and permanent data loss could occur.

•Never remove a drive while the controller is rebuilding another drive. A drive’s online LED flashes green while it is being rebuilt. The controller requires the data from all other drives to rebuild the replacement drive.

•If the system has an online spare drive, wait for it to complete rebuilding before replacing the failed drive. When a drive fails, the online spare becomes active and begins rebuilding as a replacement drive. After the online spare has completed Automatic Data Recovery (the online LED is continuously lit), replace the failed drive with a new replacement drive. Do not replace the failed drive with the online spare. The system automatically rebuilds the replacement drive and resets the spare drive to an available state.

•If you replace a drive while the system is off, it may be necessary to rebuild the replaced drive.

HP StorageWorks Modular Smart Array 500 System Maintenance and Service Guide

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