Non-disruptive controller replacement in network storage systems

Abstract

A network-based storage system includes multiple storage devices and system controllers. Each storage device in multiple aggregates of storage devices can include ownership portion(s) that are configured to indicate a system controller to which it belongs. First and second system controllers can form an HA pair, and can be in communication with each other, the storage devices, and a separate host server. A first system controller controls an aggregate of storage devices and can facilitate an automated hotswap replacement of a second system controller that controls another aggregate of storage devices with a separate third system controller that subsequently controls the other aggregate of storage devices. The first system controller can take over control of the second aggregate of storage devices during the automated hotswap replacement of the second system controller, and can exchange system identifiers and ownership portion information with the separate third system controller automatically during the hotswap.