DATA PROCESSOR STORAGE SYSTEMS WITH DYNAMIC RESYNCHRONIZATION OF MIRRORED LOGICAL DATA VOLUMES SUBSEQUENT TO A STORAGE SYSTEM FAILURE

摘要

There is provided a system for dynamically resynchronizing a storage systemmade up of aplurality of mirrored logical volumes respectively divided into a plurality ofmirrored logical datapartitions in the event of a system failure. Immediately after the correctionof the problem causingthe failure, means start to resynchronize the plurality of logical volumes butwithout waiting for theresynchronization to be completed; means access data from a data partition inone of said logicalvolumes. Then there are means for determining whether the portion of thelogical volume containingthe accessed partition has already been resynchronized, together with meansresponsive to thesedetermining means for replacing the corresponding data in the other mirroredpartitions in the logicalvolume with the accessed data, in the event that the portion of the logicalvolume has not beenresynchronized. The means for replacing the data in the other mirroredpartitions in the logicalvolume containing the accessed partition may replace the data prior toresynchronization of thelogical volume or it may replace the data during the subsequentresynchronization of the logicalvolume. In the implementation where the data in the other mirrored partitionsis replaced duringresynchronization, then there is provided interim means responsive to theaccessing of data from thedata partition in said logical volume for indicating the partition asaccessible and for indicating theother mirrored partitions in the logical volume as inaccessible.