NonStop Operating System Event Management Programming Manual

HP NonStop Operating System Event Management Programming Manual—520372-020
21-1
21 DBIOPROC Event Messages
(ZDIO)
This section describes the event messages generated by the Direct Bulk I/O Support
Procedures (DBIOPROC) subsystem. These event messages are also known as DIO
(ZDIO) event messages.
DBIOPROC is one of several subsystems that work together to provide Direct Bulk I/O
to enhance system performance. With Direct Bulk I/O, which is transparent to
applications, disk and tape bulk data is transferred directly over ServerNet between an
application data buffer, in any processor, and a storage controller under direction from
the controlling input/output process (IOP) in the same or a different processor.
Otherwise, with normal I/O, application data always flows through an intermediate
buffer in the processor of the controlling IOP.
The DBIOPROC event messages are generated to report conditions encountered that
are expected to occur only infrequently. Most of these are error conditions. Since the
recovery method for Direct Bulk I/O errors is to revert to normal I/O, none of these
events are considered critical. These event messages are reported to the EMS through
the service event logger ($ZLOG). These messages are viewable using the TSM EMS
Event Viewer application.
Topics:

Common Definitions on page 21-2

Description of DBIOPROC Event Messages on page 21-5
Table 21-1. DBIOPROC Event Messages
Event Number and Symbolic Name Description
1: ZDIO-EVT-ERROR-RTRN-RCVD
The DBIOPROC subsystem received an
unexpected return code from a call to another
procedure.
2: ZDIO-EVT-HW-XSUM-SW-FIXED
A checksum error detected using hardware
checksum did not recur when the checksum
operation was repeated using software.
3: ZDIO-EVT-QUARANTINE-START
A quarantine time period has started during which a
specific set of ServerNet addresses is unavailable
for continued use or reallocation.
4: ZDIO-EVT-QUARANTINE-END
The quarantine time period has ended.
5: ZDIO-EVT-SECTOR-XSUM
A sector checksum error has been detected.
6: ZDIO-EVT-STRUCTURED-XSUM
A structured block checksum error has been
detected.
7: ZDIO-EVT-STRUCTURED-RSN
A file-relative sector number within structured block
data read from disk into the application buffer was
not as expected.