Mirroring of a logical storage unit initially associated with a first controller is performed, where the first log segment associated with the first controller is maintained of writes by the first controller to the logical storage unit. The first log segment is for use in mirroring writes to a mirror system. Control of the logical storage unit is transferred from the first controller to at least a second controller, and in response to the transfer, a first marker is provided in the first log segment to enable the mirror system to synchronize mirrored writes corresponding to writes to the logical storage units by the first controller and at least a second controller.
