Diagnosing System Failures

In some cases, the IBISNAP snapshot enables problems to be solved on the spot, and in other cases it makes obtaining a dump unnecessary. However, in other cases dumps and/or traces are required.

By default, each IBISNAP snapshot is written to a separate class A SYSOUT file. The SYSOUT class can be changed by specifying IBISNAP in the MSO configuration file (see The MSO Configuration File). These SYSOUT files are closed and freed as soon as they are written.

If, instead, ddname IBISNAP is allocated in the MSO JCL, then this allocation is used, as is, for each abend. For SYSOUT files, this means that all IBISNAP snapshots produced by an MSO job are contained in a single SYSOUT file. For files allocated to DASD, you must specify DISP=MOD to prevent the snapshots from overwriting one another. Allocating ddname IBISNAP in the MSO JCL overrides the specification of IBISNAP in the MSO configuration file.

An IBISNAP snapshot contains a summary box, describing the system environment, the abend itself, the exact version and level of MSO, and information about the failing task. This is followed by a formatted dump of various MVS, MSO, and FOCUS control blocks and data areas. Finally, an image of the last screen written to the abending user's terminal is printed.

The following is an example of the summary box, taken from an actual abend, with a description of each of the fields in the summary:

Summary of the Environment

***************************************
* CPU: FF0123459021 0000              *
* MVS: ESA SP4.1.0 IPO1               *
* CVTOPTS: HIPER UCBSV COMDS MVPG     *
* DFP: 3.2.0 * * DATE: 93.112         *
* TIME: 16:20:07                      *
***************************************

where:

CPU

Is the CPUID and processor number.

MVS

Is the operating system level and MVS's name.

CVTOPTS

Describes the hardware features.

DFP

Is the release of DFP.

Date

Is the date the snapshot was produced.

TIME

Is the time the snapshot was produced.

About the Abend

****************************************
* JOB: MSOUSR1 JOB07622 * * ASID: 002B *
* APFAUTH: ON                          *
* TASK: SSFOC                          *
* TCB: 009CB308                        *
* MODULE: F$ROOT +000002BA             *
* PROGRAM: ???????? +03ACF8D2          *
* ABEND: S0C1 U0000 REASON=00000001    *
* PSW: 078D1200 83ACF8D2               *
* CMD: (0000)                          *
****************************************

where:

JOB

Is the Jobname and JES jobid.

ASID

Is the address space number, in hexadecimal.

APFAUTH

Identifies whether MSO is running APF-authorized.

TASK

Is the name of the failing task.

TCB

Is the failing task's TCB address.

MODULE

Is the abending load module & offset.

PROGRAM

Is the program in module (if known).

ABEND

Is the abend code and reason code.

PSW

Is the PSW at the time of abend.

CMD

Is the failing instruction.

This section of the box above is the first line of attack in troubleshooting an abend. The module, program, offset, and abend code lines make it possible to see whether the abend is a known one or not.

About the MSO Address Space

***************************************
* MSO VER: 04/16/93 9304              *
***************************************

where:

MSO VER

Is the release date and put level of MSO.

About the Failing Task

****************************************
* SERVER: FOCUS                        *
* USERID: JSMITH                       *
* NAME: JOHN SMITH                     *
* ACCOUNT:                             *
* LOGGED: 93.112 16:19:19              *
* PRTYGRP: 07                          *
* SECID: JSMITH                        *
* COMMID: T37CT17                      *
* ACCESS: VTAM                         *
* LU2NAME: FOCUS1                      *
****************************************

where:

SERVER

Is the name of the server the user logged on to.

USERID

Is the logon userid of the failing task.

NAME

Is the name associated with the SECID by the security system.

ACCOUNT

Is the name of the account. There is no account if the field is blank.

LOGGED

Date and time of user logon.

PRTYGRP

Is the MSO priority group.

SECID

Is the security userid.

COMMID

If a VTAM session, the user's terminal's luname. If a CICS session, the user's terminal name. If a TSO session, the user's TSO userid.

ACCESS

Is the logon access method (VTAM, CICS, or TSO).

LU2NAME

Is the MSO region's VTAM applid.

Following the above summary information is several pages of information intended for Information Builders support personnel, containing formatted images of relevant IBM, MSO, and FOCUS control blocks and data areas.

Last screen written to the terminal:

+ Output-------------------------------------------------------(MORE)-->+
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
+-----------------------------------------------------------------------+
                                                        + History------>+
                                                        | >TED          |
+ FOCUS Command------------------------------------------------  ------+
|                                                                       |
|                                                                       |
|                                                                       |
|                                                                       |
+-----------------------------------------------------------------------+

If the failing task was a user session with an associated terminal, the last item in the snapshot will be an image of the last screen written to the terminal. This will often be of use in identifying what was happening at the application level at the time of abend.

This screen image may be suppressed, if desired, by application of the IBISNAP zap, as documented in Site-Specific Customizations.