Abstract: A request is received to upgrade firmware for disk array enclosures (DAEs). Each DAE is reachable by a host server using first and second paths. The first path extends from a first port of a first HBA of the host server to each of a set of first input/output modules (IOMs) in the DAEs. The first IOMs have first SAS expanders to which storage disks are connected. A flag is set in firmware of each first IOM that causes SMP and SES protocol services of a DAE to mark each respective storage disk connected to each respective SAS expander of the first SAS expanders as vacant. During the firmware upgrade, advertising to a SAS driver topology change events indicating that a storage disk has been removed or added is withheld based on the flag.

Abstract: A request is received to upgrade firmware for disk array enclosures (DAEs). Each DAE is reachable by a host server using first and second paths. The first path extends from a first port of a first HBA of the host server to each of a set of first input/output modules (IOMs) in the DAEs. The first IOMs have first SAS expanders to which storage disks are connected. A flag is set in firmware of each first IOM that causes SMP and SES protocol services of a DAE to mark each respective storage disk connected to each respective SAS expander of the first SAS expanders as vacant. During the firmware upgrade, advertising to a SAS driver topology change events indicating that a storage disk has been removed or added is withheld based on the flag.

Abstract: A system having: a midplane having air flow channels therein; a disk drive mounted to a first side of the midplane; and a temperature sensors mounted to the midplane. The system includes a pair of electrical chassis connected to a second side of the midplane. A first one of the chassis has therein: a fan; and a fan controller for controlling speed of the fan in response to a temperature control signal. A second one of the chassis has therein: a microprocessor for: detecting temperature signals produced by the temperature sensors; comparing differences between the detected temperature signals; and selecting one of the detected temperature control signal from the compared differences as the temperature control signal. A faulty one of the temperature sensors is detected by: selecting one of the detected temperature control signal as the faulty one of the plurality of temperature sensors from the compared differences.

Abstract: A system having: a midplane having air flow channels therein; a disk drive mounted to a first side of the midplane; and a temperature sensors mounted to the midplane. The system includes a pair of electrical chassis connected to a second side of the midplane. A first one of the chassis has therein: a fan; and a fan controller for controlling speed of the fan in response to a temperature control signal. A second one of the chassis has therein: a microprocessor for: detecting temperature signals produced by the temperature sensors; comparing differences between the detected temperature signals; and selecting one of the detected temperature control signal from the compared differences as the temperature control signal. A faulty one of the temperature sensors is detected by: selecting one of the detected temperature control signal as the faulty one of the plurality of temperature sensors from the compared differences.

Abstract: A system having: a midplane having air flow channels therein; a disk drive mounted to a first side of the midplane; and a temperature sensors mounted to the midplane. The system includes a pair of electrical chassis connected to a second side of the midplane. A first one of the chassis has therein: a fan; and a fan controller for controlling speed of the fan in response to a temperature control signal. A second one of the chassis has therein: a microprocessor for: detecting temperature signals produced by the temperature sensors; comparing differences between the detected temperature signals; and selecting one of the detected temperature control signal from the compared differences as the temperature control signal. A faulty one of the temperature sensors is detected by: selecting one of the detected temperature control signal as the faulty one of the plurality of temperature sensors from the compared differences.