setmqxr (set MQTT server properties)

Use the setmqxr properties command to configure MQTT server properties.

The command allows you to individually configure the properties that are specified in the following configuration files:

mqxrtraceOff.properties
mqxrtraceOn.properties
java.properties
mqxr_unix.properties
mqxr_win.properties

Notes:

From IBM® MQ 9.4.4, the MQTT server only supports FIPS 140-3.FIPS 140-2 is no longer supported.
To enable FIPS 140-3, you need to include two new JVM properties in the java.properties file. For more information, see Table 1.
FIPS is not supported on Linux® s390.

Syntax

Required parameters

-m QMgrName

The queue manager you are setting MQTT properties for.

-k name

The name of the MQTT property that you want to set. You must combine this parameter with one of the following parameters:

-d: Delete the specified MQTT property.
-v value: The value that the property is set to.
-r: Reset the specified property to its default value.

Optional parameters

-l: Enable verbose logging. Diagnostic information is written to a log file.

The following table lists some of the properties can be configured by the setmqxr properties command on all platforms. A full list of properties that can be configured using this command can be viewed by using the dspmqxr command.

Table 1. MQTT Server properties and values
Property	Description
-Dcom.ibm.mq.MQXR.GenerateHeapDump	Specifies whether or not a Java heap dump is generated when the service encounters a low memory exception. It accepts a value of true and false. If you do not specify a value for this attribute, the default value of false is used.
-Dcom.ibm.mq.MQXR.GenerateJavaDump	Specifies whether or not a Java core dump is generated when an FDC is generated. It accepts a value of true and false. If you do not specify a value for this attribute, the default value of false is used.
-Xms<`size`>	The -Xms option sets the initial and minimum Java heap size. The size is specified in megabytes. For example, -Xms512m. To configure this property, the -v argument must be left empty.
-Xmx<`size`>	This option sets the maximum Java heap size. The size is specified in megabytes. For example, `-Xmx1024m`. To configure this property, the -v argument must be left empty.
handlers	Specifies the log file handler to use. It accepts the values `com.ibm.mq.util.logging.MQErrorLogFileHandler`, `com.ibm.mq.util.logging.MQJSONErrorLogFileHandler`, `java.util.logging.MemoryHandler`, and `com.ibm.mq.util.logging.MQCommonServicesHandler`. A combination of these can also be used by specifying a comma-separated list.
com.ibm.mq.MQXR.Workers	The number of server workers the service should use. If not set, the value defaults to the number of processors.
com.ibm.mq.MQXR.MQIBindType	The binding type for the service, one of: FASTPATH, SHARED, or ISOLATED. The default is FASTPATH.
-Dsemeru.fips	Specifies that FIPS is enabled when the value is set to TRUE. The default value is FALSE.
-Dsemeru.customprofile	Defines the cryptographic provider to use with FIPS 140-3. If the MQ Telemetry server is running with FIPS 140-3, set this property to OpenJCEPlusFIPS.

Return codes

Table 2. Return code identifiers and descriptions
Return code	Description
0	Command successful
>0	Command not successful

Examples

The following command enables JSON formatted logs for MQTT for the queue manager QM1:

setmqxr properties -m QM1 -k handlers -v com.ibm.mq.util.logging.MQJSONErrorLogFileHandler

The following command resets the logging format back to its default setting of plain text logs:
```
setmqxr properties -m QM1 -k handlers -r
```

If SSLFIPS is enabled in the queue manager without setting both the Dsemeru Java properties, the MQTT service does not start and the following error message is logged:

AMQXR2125E: SSLFIPS property is set to YES in the Queue Manager configuration but the FIPS 140-3 JVM system 
properties -Dsemeru.fips=true and -Dsemeru.customprofile=OpenJCEPlusFIPS are not set in the java.properties file.