Log-related properties are described in Table 16–10.
Set the logging level.
Set the output channel (file, console, or both) for one or more logging categories.
If you log output to a file, configure the rollover criteria for the file.
You complete these steps by setting Logger properties. You can do this in one of two ways:
Change or add Logger properties in the config.properties file for a broker before you start the broker.
Specify Logger command line options in the imqbrokerd command that starts the broker. You can also use the broker option -D to change Logger properties (or any broker property).
Options passed on the command line override properties specified in the broker instance configuration files. The following imqbrokerd options affect logging:
Logging interval for broker metrics, in seconds
Logging level (ERROR, WARNING, INFO, or NONE)
Silent mode (no logging to console)
Log all messages to console
The following sections describe how you can change the default configuration in order to do the following:
Change the output channel (the destination of log messages)
Change rollover criteria
By default, error and warning messages are displayed on the terminal as well as being logged to a log file. (On Solaris, error messages are also written to the system’s syslog daemon.)
You can change the output channel for log messages in the following ways:
To have all log categories (for a given level) output displayed on the screen, use the -tty option to the imqbrokerd command.
To prevent log output from being displayed on the screen, use the -silent option to the imqbrokerd command.
Use the imq.log.file.output property to specify which categories of logging information should be written to the log file. For example,
imq.log.file.output=ERROR
Use the imq.log.console.output property to specify which categories of logging information should be written to the console. For example,
imq.log.console.output=INFO
On Solaris, use the imq.log.syslog.output property to specify which categories of logging information should be written to Solaris syslog. For example,
imq.log.syslog.output=NONE
Before changing Logger output channels, you must make sure that logging is set at a level that supports the information you are mapping to the output channel. For example, if you set the logging level to ERROR and then set the imq.log.console.output property to WARNING, no messages will be logged because you have not enabled the logging of WARNING messages.
There are two criteria for rolling over log files: time and size. The default is to use a time criteria and roll over files every seven days.
To change the time interval, you need to change the property imq.log.file.rolloversecs. For example, the following property definition changes the time interval to ten days:
imq.log.file.rolloversecs=864000
To change the rollover criteria to depend on file size, you need to set the imq.log.file.rolloverbytes property. For example, the following definition directs the broker to rollover files after they reach a limit of 500,000 bytes
imq.log.file.rolloverbytes=500000
If you set both the time-related and the size-related rollover properties, the first limit reached will trigger the rollover. As noted before, the broker maintains up to nine rollover files.
You can set or change the log file rollover properties when a broker is running. To set these properties, use the imqcmd update bkr command.
This section describes the procedure for using broker log files to report metrics information. For general information on configuring the Logger, see Configuring and Using Broker Logging.
Configure the broker’s metrics generation capability:
Confirm imq.metrics.enabled=true
Generation of metrics for logging is turned on by default.
Set the metrics generation interval to a convenient number of seconds.
imq.metrics.interval=interval
This value can be set in the config.properties file or using the -metrics interval command line option when starting up the broker.
Confirm that the Logger gathers metrics information:
imq.log.level=INFO |
This is the default value. This value can be set in the config.properties file or using the -loglevel level command line option when starting up the broker.
Confirm that the Logger is set to write metrics information to the log file:
imq.log.file.output=INFO |
This is the default value. It can be set in the config.properties file.
Start up the broker.
The following shows sample broker metrics output to the log file:
[21/Jul/2004:11:21:18 PDT] Connections: 0 JVM Heap: 8323072 bytes (7226576 free) Threads: 0 (14-1010) In: 0 msgs (0bytes) 0 pkts (0 bytes) Out: 0 msgs (0bytes) 0 pkts (0 bytes) Rate In: 0 msgs/sec (0 bytes/sec) 0 pkts/sec (0 bytes/sec) Rate Out: 0 msgs/sec (0 bytes/sec) 0 pkts/sec (0 bytes/sec) |
For reference information about metrics data, see Chapter 20, Metrics Information Reference
You can monitor physical destinations by enabling dead message logging for a broker. You can log dead messages whether or not you are using a dead message queue.
If you enable dead message logging, the broker logs the following types of events:
A physical destination exceeded its maximum size.
The broker removed a message from a physical destination, for a reason such as the following:
The destination size limit has been reached.
The message time to live expired.
The message is too large.
An error occurred when the broker attempted to process the message.
If a dead message queue is in use, logging also includes the following types of events:
The broker moved a message to the dead message queue.
The broker removed a message from the dead message queue and discarded it.
The following is an example of the log format for dead messages:
[29/Mar/2006:15:35:39 PST] [B1147]: Message 8-129.145.180.87(e7:6b:dd:5d:98:aa)- 35251-1143675279400 from destination Q:q0 has been placed on the DMQ because [B0053]: Message on destination Q:q0 Expired: expiration time 1143675279402, arrival time 1143675279401, JMSTimestamp 1143675279400 |
Dead message logging is disabled by default. To enable it, set the broker attribute imq.destination.logDeadMsgs.