Method and computer for data set separation

A computer that allocates a first data set to a first storage volume of a storage system, wherein said storage system includes a plurality of storage resources that each contain one or more storage volumes, said computer comprising:

• first means for identifying at least one second data set from which said first data set is to be separated;
• second means for identifying any of said plurality of storage resources and any volume thereof that contains said second data set;
• and
• third means for forming an eligible volume list for selection of said first storage resource according to a policy such that any storage volume identified by said second means is excluded from said list, whereby a failure in either a storage resource that contains said first storage volume or any storage resource identified by said second means has a minimal impact on the other thereof.

A memory media for causing a computer to allocate a first data set to a first storage volume of a storage system, wherein said storage system includes a plurality of storage resources that each contain one or more storage volumes, said memory media comprising:

• first means for controlling said computer to perform a first operation of identifying at least one second data set from which said first data set is to be separated;
• second means for controlling said computer to perform a second operation of identifying any of said plurality of storage resources and any volume thereof that contains said second data set;
• and
• third means for controlling said computer to perform a third operation of forming an eligible volume list for selection of said first storage resource according to a policy such that any storage volume identified by said second operation is excluded from said list, whereby a failure in either a storage resource that contains said first storage volume or any storage resource identified by said second operation has a minimal impact on the other thereof.