Verified write command in active-active replication

A storage system, comprising:

• one or more storage devices, and
• at least one processor configured to perform the operations of:
• receiving a first request to perform an atomic write operation at a specified address in a volume, the first request being received from a host device;
• placing a read-write lock on a first instance of the volume that is stored in the one or more storage devices, and executing the atomic write operation on the first instance of the volume;
• transmitting, to a peer storage system, a second request to perform the atomic write operation on a second instance of the volume that is stored at the peer storage system;
• detecting whether an error condition is present that is associated with the second request;
• and
• when the error condition is present, comparing a first data item that is stored at the specified address in the first instance of the volume with a second data item that is stored at the specified address in the second instance of the volume, and, when the first data item matches the second data item, transmitting an acknowledgment to the host device indicating that the first request has been completed successfully.

A method for use in an active-active storage cluster having first a storage array and a second storage array, the method comprising:

• receiving, at the first storage array, a first request to perform an atomic write operation at a specified address in a volume, the first request being received from a host device;
• placing a read-write lock on a first instance of the volume that is stored at the first storage array;
• transmitting, to the second storage array, a second request to perform the atomic write operation on a second instance of the volume that is stored at the second storage array;
• and
• detecting whether an error condition is present that is associated with the second request;
• when the error condition is present, comparing a first data item that is stored at the specified address in the first instance of the volume with a second data item that is stored at the specified address in the second instance of the volume, and, when the first data item does not match the second data item, copying the second data item to the specified address in the first instance of the volume, and transmitting an acknowledgment to the host device indicating that the first request has been completed successfully.