摘要 |
In a storage environment or storage area network having multiple host devices and at least one storage array, the host devices access logical data volumes stored on the storage array through array controllers disposed in the storage array. Multiple host devices can request access to shared ones of the logical data volumes through multiple paths to multiple array controllers, but each logical data volume is controlled or owned by only one array controller at a time. Thus, ownership of shared logical data volumes is transferred between the array controllers as necessary on behalf of the requesting host devices. To prevent ownership transfers from occurring too often, however, ownership of the logical data volumes is made exclusive, or "sticky," for a period of time after each transfer. During the exclusive ownership period of time, the ownership cannot be transferred. After expiration of the exclusive ownership period of time, ownership of the affected logical data volume is transferred if the transfer does not cause another host device to lose access to the same logical data volume, unless priorities between competing host devices permit one host device to take access away from the other host device.
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