Method and apparatus for testing a storage system head in a clustered failover configuration

A method comprising:

• assessing an operational status of a second storage server head by executing a diagnostic process by a diagnostic kernel in a first storage server head by transmitting a plurality of packets onto an interconnect using a Gigabit Ethernet protocol, wherein the interconnect comprises a passive backplane coupling the first storage server head to the second storage server head, the first and second storage server heads being independently operable in a cluster failover configuration to provide a host with access to a plurality of mass storage devices of a storage network, wherein each of the plurality of mass storage devices is coupled to the interconnect that couples the first storage server head to the second storage server head, wherein each of the first storage server head and the second storage server head comprises an identical diagnostic kernel, either of which is operable to initiate the diagnostic process to communicate with the other storage server head via the passive backplane;
• receiving, at the first storage server head, zero or more of the plurality of packets back from the second storage server head via the interconnect, wherein the second storage server head receives the plurality of packets and responds to communicate the operational status of the second storage server head;
• verifying, at the first storage server head, content of each of the plurality of packets received back from the second storage server head;
• and
• determining the operational status of the second storage server head based on results of said receiving and said verifying,
• wherein each of the first and second storage server heads is configurable to receive both file-level access requests and block-level access requests to store data onto the mass storage devices, to provide one of a storage area network and a network attached storage as the storage network according to a user selection after deployment.

A method comprising:

• assessing an operational status of a second storage server head by executing a diagnostic process by a diagnostic kernel in a first storage server head by transmitting a plurality of packets onto an interconnect using a Gigabit Ethernet protocol, wherein the interconnect comprises a passive backplane coupling the first storage server head to the second storage server head, each of the plurality of packets having a header set to a predetermined value, the first and second storage server heads being independently operable in a cluster failover configuration to provide a host with access to a plurality of mass storage devices of a storage network, wherein each of the first storage server head and the second storage server head comprises an identical diagnostic kernel,
• either of which is operable to initiate the diagnostic process to communicate with the other storage server head via the passive backplane;
• receiving zero or more of the plurality of packets at the second storage server head via the interconnect, wherein the second storage server head receives the plurality of packets and responds to communicate the operational status of the second storage server head;
• for each of the plurality of packets received at the second storage server head, determining in the second storage server head whether a header in each of the packets matches the predetermined value;
• retransmitting each of the plurality of packets which was received at the second storage server head and which has the header matching the predetermined value, from the second storage server head back to the first storage server head via the interconnect, to respond to the received packets without further processing said packet in the second storage server head;
• receiving at least some of the retransmitted plurality of packets at the first storage server head;
• determining in the first storage server head whether all of the plurality of packets have been returned by the second storage server head;
• verifying content of the retransmitted packets received at the first storage server head relative to the plurality of packets;
• generating a report of the operational status of the second storage server head based on results of said determining and said verifying;
• and
• outputting the report to a user, wherein each of the first and second storage server heads is configurable to receive both file-level access requests and block-level access requests to store data onto the mass storage devices, to provide one of a storage area network and a network attached storage as the storage network according to a user selection after deployment.

A storage system comprising:

• a first storage server head;
• and
• a second storage server head coupled to the first storage server head via an interconnect, the interconnect comprising a passive backplane, the first and second storage server heads being configured in a cluster failover configuration to redundantly provide a host with access to a plurality of mass storage devices of a storage network, the first storage server head being configured to assess an operational status of the second storage server head by executing a diagnostic process to verify the presence of a communication link with the second storage server head while the second storage server head is in a mode for providing the host with access to the plurality of mass storage devices, wherein a diagnostic kernel in the first storage server head sends a signal to the second storage server head over the passive backplane using a Gigabit Ethernet protocol and the second storage server head receives the signal and responds to communicate the operational status of the second storage server head, wherein each of the plurality of mass storage devices is coupled to the interconnect coupling the first storage server head to the second storage server head, wherein each of the first storage server head and the second storage server head comprises an identical diagnostic kernel, either of which is operable to initiate the diagnostic process to communicate with the other storage server head via the passive backplane,
• wherein each of the first and second storage server heads is configurable to receive both file-level access requests and block-level access requests to store data onto the mass storage devices, to provide one of a storage area network and a network attached storage as the storage network according to a user selection after deployment.

A storage system comprising:

• an enclosure;
• a passive backplane installed within the enclosure;
• a first storage server head within the enclosure, implemented on a first single circuit board coupled to the passive backplane, to control access by an external host to a plurality of mass storage devices of a storage network;
• and
• a second storage server head within the enclosure, implemented on a second single circuit board coupled to the passive backplane, to control access by the external host to the plurality of mass storage devices and operable redundantly to the first storage server head, the first storage server head and the second storage server head being coupled to communicate with each other via the passive backplane using a Gigabit Ethernet protocol, the first storage server head being configured to assess an operational status of the second storage server head by executing a diagnostic process to verify the presence of a communication link with the second storage server head while the second storage server head is in a mode for providing the external host with access to the plurality of mass storage devices, wherein a diagnostic kernel in the first storage server head sends a signal to the second storage server head and the second storage server head receives the signal and responds to communicate the operational status of the second storage server head, wherein each of the plurality of mass storage devices is coupled to a same interconnect coupling the first storage server head to the second storage server head, wherein each of the first storage server head and the second storage server head comprises an identical diagnostic kernel, either of which is operable to initiate the diagnostic process to communicate with other storage server head via the passive backplane,
• wherein each of the first and second storage server heads is configurable to receive both file-level access requests and block-level access requests to store data onto the mass storage devices, to provide one of a storage area network and a network attached storage as the storage network according to a user selection after deployment.