Sas driver-level systems and methods for upgrading firmware for disk array enclosures (daes)

A system comprising:

• a processor;
• and memory configured to store one or more sequences of instructions which, when executed by the processor, cause the processor to carry out the steps of:
• receiving a request to upgrade firmware for a plurality of disk array enclosures (DAEs) in a storage system, wherein each DAE is reachable by a host server using first and second paths,
• wherein the first path extends from a first port of a first host bus adapter (HBA) of the host server to each of a plurality of first input/output modules (IOMs) in the DAEs, the plurality of first IOMs having first serial attached SCSI (SAS) expanders to which a plurality of storage disks are connected, and
• the second path extends from a second port of a second HBA of the host server to each of a plurality of second IOMs in the DAEs, the plurality of second IOMs having second SAS expanders to which the plurality of storage disks are connected;
• changing the first port from a first state during which a SAS driver exposes all topology change events of the storage system to an operating system (OS) of the host server to a second state during which the SAS driver does not expose all of the topology change events to the OS;
• upgrading firmware of the plurality of first IOMs;
• and
• after the upgrading the firmware, changing the first port from the second state to the first state.

A computer program product, comprising a non-transitory computer-readable medium having a computer-readable program code embodied therein, the computer-readable program code adapted to be executed by one or more processors to implement a method comprising:

• receiving a request to upgrade firmware for a plurality of disk array enclosures (DAEs) in a storage system, wherein each DAE is reachable by a host server using first and second paths,
• wherein the first path extends from a first port of a first host bus adapter (HBA) of the host server to each of a plurality of first input/output modules (IOMs) in the DAEs, the plurality of first IOMs having first serial attached SCSI (SAS) expanders to which a plurality of storage disks are connected, and
• the second path extends from a second port of a second HBA of the host server to each of a plurality of second IOMs in the DAEs, the plurality of second IOMs having second SAS expanders to which the plurality of storage disks are connected;
• changing the first port from a first state during which a SAS driver exposes all topology change events of the storage system to an operating system (OS) of the host server to a second state during which the SAS driver does not expose all of the topology change events to the OS;
• upgrading firmware of the plurality of first IOMs;
• and
• after the upgrading the firmware, changing the first port from the second state to the first state.