Validation of write data subsequent to destaging to auxiliary storage for completion of peer to peer remote copy

A system, comprising:

• a memory;
• and
• a processor coupled to the memory, wherein the processor performs operations, the operations performed by the processor comprising:
• receiving, by a primary storage controller, a transaction to perform a write command from a host, to write data that is to be controlled by the primary storage controller;
• in response to determining that a user has requested that the data to be written comprises critical data that is to be protected more securely than data that is not critical data and that the transaction is to be guaranteed on both the primary storage controller and a secondary storage controller, performing:
• writing the data to a local storage of the primary storage controller and subsequently destaging the data from the local storage of the primary storage controller to store the data in an auxiliary storage of the primary storage controller;
• transmitting the data to the secondary storage controller for writing the data to a local storage of the secondary storage controller and subsequently destaging the data from the local storage of the secondary storage controller to store the data in an auxiliary storage of the secondary storage controller;
• and
• comparing the data stored in the auxiliary storage of the primary storage controller to the data stored in the auxiliary storage of the secondary storage controller to determine whether the write command is successfully executed;
• and
• in response to determining that the user has not requested that the data to be written comprises critical data and that the transaction does not have to be guaranteed on both the primary storage controller and the secondary storage controller, performing a peer to peer remote copy of the data from the primary storage controller to the secondary storage controller, wherein in the peer to peer remote copy an indication is provided to the host that the write command is successfully executed without performing at least the comparing.

A computer program product, the computer program product comprising a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code configured to perform operations, the operations comprising:

• receiving, by a primary storage controller, a transaction to perform a write command from a host, to write data that is to be controlled by the primary storage controller;
• in response to determining that a user has requested that the data to be written comprises critical data that is to be protected more securely than data that is not critical data and that the transaction is to be guaranteed on both the primary storage controller and a secondary storage controller, performing:
• writing the data to a local storage of the primary storage controller and subsequently destaging the data from the local storage of the primary storage controller to store the data in an auxiliary storage of the primary storage controller;
• transmitting the data to the secondary storage controller for writing the data to a local storage of the secondary storage controller and subsequently destaging the data from the local storage of the secondary storage controller to store the data in an auxiliary storage of the secondary storage controller;
• and
• comparing the data stored in the auxiliary storage of the primary storage controller to the data stored in the auxiliary storage of the secondary storage controller to determine whether the write command is successfully executed;
• and
• in response to determining that the user has not requested that the data to be written comprises critical data and that the transaction does not have to be guaranteed on both the primary storage controller and the secondary storage controller, performing a peer to peer remote copy of the data from the primary storage controller to the secondary storage controller, wherein in the peer to peer remote copy an indication is provided to the host that the write command is successfully executed without performing at least the comparing.