DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Maintenance Object Repair Procedures
9-546DISK (MSS Disk Circuit Pack)
9
System Technician-Demanded T ests: Descripti ons
and Error Codes
Always investigate tests in the order p resented in the table below when
inspecting errors in the sy stem. By clearing error cod es associated with the

Disk

Reset Test
, for example, you may also clear errors g enerated from other tests in
the testing sequence.
Disk Reset Test (#809 and #894)
The Disk Reset Test consists of the following steps controlled by firmware on the
Host Adapter Circuit (located on the MSSNET circuit pack):
■Disk Drive reset: A SCSI BUS DEVICE RESET message is transmitted to
the Disk circuit pac k to reset it.
■Presence test: A SCSI INQUIRY command is sent to the Disk Drive to
attempt to query it. If the Disk Drive is p resent, it will return information
about the device typ e, whether or not its medium is removable,
compatibility with estab lished standards, vend or and produc t IDs, and
other miscellaneous information.
■Start unit: This starts the disk drive spin ning.
■Capacity test: A SCSI READ CAPACITY command is sent to the Disk
Drive. It returns with the logical b lock address and t he block length of the
last logical bloc k on the medium. This is necessary to restore the
information lost after the reset and verify that the devic e can be accessed .
A SCSI READ DATA BUFFERS command is sent to the Disk Drive. This
returns the size of the controller memory data b uffers.
Order of Investigation Short Test
Sequence Long Test
Sequence Reset Board
Sequence D/ND1
1. D = Destructive; ND = Nondestruc tive
Disk Reset Test (#809) X X ND
Disk Diagnostic Test (#813) X X ND
Disk Looparound Test (#814) X X ND
Disk Status Test (#815) X X ND
Disk Firmware Error Counters
Read and Clear Test (#812) XX ND
Disk Write-Read Test (#810) X ND
Disk Audit Test (#811) X ND
Disk Reset Test (#894) X ND