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SCSI Enclosure Services (SES) devices contains a number of elements, each of which is defined by a one byte SCSI element code. There are many different element codes defined to cover various devices as shown in the list below.
The SCSI initiator communicates with an SES device using two SCSI commands, Send Diagnostic and Receive Diagnostic Results. The most common SES elements are power-supply, cooling-fan, temperature-sensor and UPS. The SCSI command protocols assume that there may be more than one of each device type so they must each be given an 8-bit address. When the SES controller is interrogated for the status of an SES element, the response includes a 4-bit status code. The most common element status codes are: 1h=OK, 2h=critical, 3h=warning, 5h=not installed.
See the SES article for a more detailed description.
When a SCSI SES controller is interrogated for the status of a SES element, the response includes a 4-bit SCSI element status code. The list of valid codes is:
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