A storage system includes a local storage array and a remote storage array. The local storage array has a host interface configured to communicate with an external host, a local storage device coupled to the host interface, and a portal device coupled to the host interface. The remote storage array has a remote storage device. The portal device of the local storage array includes local circuitry configured to communicate with (i) the external host through the host interface of the local storage array and (ii) the remote storage device of the remote storage array through a communications pathway. The portal device is configured to behave as a local disk to the external host to enable the external host to perform data mirroring operations between the local storage device and the remote storage device through the host interface.