Use component trace (CTRACE) to capture and display trace
data in trace datasets. Use error log stream to review records that
contain error information when WebSphere® Application
Server for z/OS® detects an unexpected condition or failure
within its own code. Use BBORBLOG to browse the error log stream.
You can use the following diagnostic tools:
- Component trace
- Error log stream
- Dump datasets
Overview of problem diagnosis
WebSphere Application
Server for z/OS uses component trace (CTRACE) to capture
and display trace data in trace datasets. WebSphere Application
Server for z/OS identifies itself to CTRACE with the short
cell name. CTRACE allows you to perform the following tasks:
- Merge multiple traces through the browse tool, including other
components such as TCP/IP and z/OS UNIX.
- Write trace data to a dataset rather than to STDOUT, keeping spool
space free.
- Better manage system resources by allowing trace data to wrap
or not wrap.
- Use CTRACE to funnel trace data from multiple address spaces to
one dataset, or have CTRACE send the trace data from each address
space to separate datasets.
- Start and stop tracing without stopping and restarting WebSphere Application Server for z/OS address
spaces.
- Use one or more datasets for capturing trace data, thus allowing
you to manage I/O more effectively.
WebSphere Application Server for z/OS also
has an error log stream that records the following error information
when WebSphere Application Server for z/OS detects
an unexpected condition or failure within its own code:
- Assertion failures
- Unrecoverable error conditions
- Vital resource failures, such as memory
- Operating system exceptions
- Programming defects in WebSphere Application Server
for z/OS code
Use the error log stream in conjunction with other facilities
available to capture error or status information—such as an
activity log, trace data, system logrec, and job log.
The WebSphere Application Server for z/OS error
log stream is a system logger application. Because the error log stream
uses the system logger, you can perform the following tasks:
- Have error information written to a coupling facility log stream,
which provides sysplex-wide error logging, or to a DASD-only log stream,
which provides single system-only error logging.
Note: There
is a significant performance penalty when using DASD-only error logging.
- Set up either a common log stream for all of WebSphere Application
Server for z/OS or individual log streams servers.
Local z/OS client
ORBs can also log data in log streams. Because the system logger APIs
are unauthorized, any application can use them. You should control
access to the log streams through a security product such as RACF®.
WebSphere Application Server for z/OS provides
a REXX EXEC (BBORBLOG) that allows you to browse
the error log stream. By default, the EXEC formats the error records
to fit a 3270 display.
Information about using the error log
stream to diagnose problems is in the Troubleshooting section of the WebSphere Application Server documentation.
General information and guidance about the system logger is in
z/OS MVS™ Setting
Up a Sysplex.
Table 1. Error
log stream information. This table will help you find WebSphere Application Server for z/OS error
log stream information.
What
is your goal? |
You
should read: |
Learn
about the system logger and understand its requirements |
z/OS MVS Setting
Up a Sysplex |
Learn
about the WebSphere Application Server for z/OS error
log stream |
This
article |
Size
the coupling facility structure space needed for the WebSphere Application
Server for z/OS error log stream |
z/OS MVS Setting
Up a Sysplex |
Define
the WebSphere Application Server for z/OS error
log stream |
|
View
the WebSphere Application Server for z/OS error
log stream |
The
Troubleshooting section of the WebSphere Application
Server documentation |
Learn
about how Java™ applications can log messages
and trace data in the error log stream |
The
Applications section of the WebSphere Application Server
documentation |
For details about problem diagnosis,
see the Troubleshooting section of the WebSphere Application
Server documentation.
Planning for component trace
To use CTRACE,
perform the following tasks:
- Specify trace options for identifying trace datasets and connecting WebSphere Application Server for z/OS address
spaces to the datasets in parmlib members.
- Update WebSphere Application Server for z/OS WebSphere variables to allow for initial
trace parameters.
- Use IPCS-CTRACE to view the trace data because you cannot read
the trace data in an ordinary editor.
Recommendation for dumps
Plan as you would
normally for system dumps. Due to the size of WebSphere Application
Server for z/OS address spaces, you might need to resize
your system dump datasets and use dynamic dump datasets.