IBM 86655RY Hardware Maintenance Manual - Page 33

To prevent data-integrity problems, the ServeRAID controllers sets the RAID level-0 logical drives to blocked during a rebuild operation. After the rebuild operation completes, you can unblock the RAID level-0 logical drives, and access them once again. Remember, however, that the logical drive might contain damaged data. Steps for recovering from defunct drives If the defunct drives are part of an array, do the following: • If more than one physical drive in an array is defunct, replace DDD drives and restore from backup. • If a rebuild operation is in progress, wait until the rebuild is complete. • If a rebuild is not in progress and only one physical drive in the array is defunct, replace the drive. Rebuilding a hot-swap drive A hot-swap rebuild refers to a rebuild operation that is started by the ServeRAID controller when it detects that a drive that is part of a RAID-I or RAID-J array and in the defunct state has been removed and reinserted on the SCSI backplane. The reinsertion of the physical drive, whether it is the same drive or a new drive, will trigger the ServeRAID controller to start the rebuild operation. During the rebuild operation, the drive being rebuilt is in the rebuild state, and the logical drive remains critical until the rebuild operation has been successfully completed. On IBM servers, when a hot-spare drive is available, the rebuild operation will begin automatically without the requirement to replace the failed drive. To start a hot-swap rebuild, do the following: 1. Without removing the drive completely, gently remove the physical drive from the server, using the handle of the hot-swap tray. If necessary, refer to the documentation that comes with your server on removing a physical drive. 2. Wait 20 seconds to allow the physical drive to completely spin down. Note: When power is removed from a hot-swap drive, the drive immediately parks the heads, locks the actuator in the "landing zone", and begins spinning down. However, the spinning down of the disk might require up to 20 seconds after power is removed. Do not move the drive while it is spinning down. Moving the drive while it is spinning down may damage the drive. 3. Gently replace into the server the physical drive that you removed. Make sure the drive is completely installed in the backplane connector. Recovering from an incomplete format of a physical drive During formatting of a physical drive, if the format process is stopped by a system reset, system shut down, power outage, or by some other means, the physical drive becomes inoperable. To enable the physical drive to communicate with the ServeRAID controller again, do the following: 1. Note the channel of the ServeRAID controller to which the physical drive is connected. 2. Note the SCSI ID of the physical drive. Diagnostics 23