Method for enabling overlapped input/output requests to a logical device from multiple hosts with explicit allegiances

A method for enabling a disk array storage facility to handle overlapped input-output requests to a single logical volume wherein the input-output request contains a plurality of predetermined parameters, said method comprising the steps of:

• A) establishing a table for the logical volume with an entry input-output requests and corresponding parameters,
• B) testing the parameters for each new input-output request with respect to the parameters for input-output request entries in the table,
• C) responding to said testing by performing one of a plurality of control functions which control functions include enabling the processing of the input-output request by the storage facility.