High availability network storage system incorporating non-shared storage suitable for use with virtual storage servers

A method comprising:

• operating a virtual storage server (VSS) in a host processing system as part of a high-availability (HA) storage cluster, by mirroring data from a local direct attached storage (DAS) storage set of the host processing system to an external processing system configured as an HA storage partner of the VSS, wherein the VSS includes a RAID layer;
• exporting a storage device of the local DAS storage set to the HA storage partner by using a proxy element in the VSS logically below the RAID layer;
• and
• importing a storage device of a remote DAS storage set to the VSS by using a proxy element in the VSS logically below the RAID layer.

A host processing system comprising:

• a processor;
• a local storage set functionally coupled to the processor, wherein the local storage set is non-shared storage;
• a network interface through which to receive over a network, from a storage client, a data access request relating to data stored in the local storage set;
• a storage operating system including a mirroring module to mirror data from the local storage set to an external processing system configured as a high-availability (HA) storage partner of the host processing system;
• an export proxy configured to operate logically below the mirroring module, to export to the HA storage partner a storage device of the local storage set;
• and
• an import proxy configured to operate logically below the mirroring module, to import and present to the storage operating system an exported storage device of a remote storage set, wherein the remote storage set is non-shared storage.