Generating the plug-in configuration in a high availability environment

In a high availability environment, we can configure the web server to generate the plug-in configuration. By doing so, you ensure that the configuration is generated by one process in the cell, regardless of other processes that might not be available.

• Establish the high availability environment. For more information, read about setting up a high availability environment.

• Use the high availability plugin-cfg generation service does not automatically disable the on demand router (ODR) plugin-cfg generation, if it is enabled. The two services are independent. It is redundant to enable both services; when you enable the high availability plugin-cfg generation service, disable any previously configured ODR plugin-cfg generation. For more information, read about configuring an ODR to dynamically update the web server plug-in configuration.

• (v8550) If we enable Intelligent Management for a web server, do not use the option to dynamically generate the plugin-cfg.xml file for that web server. Dynamically generating the plugin-cfg.xml file overwrites the Intelligent Management settings in the plugin-cfg.xml file.

• Define a set of custom properties at the cell level for each plugin-cfg.xml file to generate. The custom properties are formatted as ODCPluginCfg<property>_<definitionID>=value, where <property> is one of the following elements:

  • OdrList

  • OutputPath

  • UpdateScript

  • OdrClusterList

  • Disabled

  The <definitionID> variable is the name of the configuration that you choose. As a result, properties ending in the same <definitionID> variable define a single generation definition within the high availability plug-in configuration generation service.

The ODCPluginCfgUpdateScript_<definitionID> value can be set with the same options as the values in the Plugin config change script text box. For more information, read about configuring an ODR to dynamically update the web server plug-in configuration.

• To generate HAPluginCfgGeneration definitions on demand:

  1. Disable automatic generation. Set the cell custom property ODCPluginCfgDisabled_<definitionID> to true.

  2. To generate a new plug-in, run this command:

     <WAS_HOME>/bin/wsadmin.sh -lang jython -f <WAS_HOME>/bin/manageODC.py generateHAPluginCfgs
     <generationDefinitionIDs> <nodeName> <serverName>

     where:

     generationDefinitionIDs

     is a list of HAPluginCfgGeneration IDs separated by commas of the form ODCPluginCfg_<definitionID>.

     nodeName

     is the name of the node that performs the generation.

     serverName

     is the process name that performs the generation. Any Intelligent Management augmented process can generate the HAPluginCfgs configuration on demand, except for XDAGENT processes. For example:

     <WAS_HOME>/bin/wsadmin.sh -lang jython -f <WAS_HOME>/bin/manageODC.py generateHAPluginCfgs
     ODCPluginCfg_1,ODCPluginCfg_2 dmgrNodeName dmgr

• To limit how often the HAPluginCfgGeneration definitions are regenerated, set the cell custom property ODCPluginCfgMinGenerationDelay with a value that represents the time in minutes between possible generations. For example:
  ODCPluginCfgMinGenerationDelay = 10

  The configured HAPluginCfgGeneration definitions are regenerated every 10 minutes at the most. If the generator receives notification to rebuild the pluginCfgs, it delays the generation of pluginCfgs written within the last 10 minutes.

• To limit how often an ODR generated plugin-cfg.xml file is regenerated, set the JVM property com.ibm.ws.odr.plugincfg.minGenerationDelay to a value that represents the time in minutes between possible generations and then cycle the ODR.

• By default, the configured static runtime weight value is used to include stopped ODR processes in a generated plugin-cfg.xml file.

• To include stopped ODR processes in a generated plugin-cfg.xml file based on the current runtime weight value (always 0), configure the following settings:

  • For the HAPluginCfgGenerator, set the cell custom property ODCPluginCfgOdrIncludeStoppedStatic to false.

  • For ODR generated plugin-cfg.xml files, set the JVM property com.ibm.ws.odr.plugincfg.odrIncludeStoppedStatic to false, and then cycle the ODR.

1. In the console, click System administration > Cell > Custom properties > New.

2. Define the following custom properties:

   (V8502) ODCPluginCfgOdrList_<definitionID>=cell1:node1:odr1,cell2:node2:*,[cell1:node3:odr3],[cell1:node4:odr4]

   The ODRs to include in the plugin-cfg.xml file. Use the asterisk (*) symbol as a valid wildcard for each path segment.odr1 and odr2 are marked as primary servers. odr3 and odr4 are marked as backup servers.

   ODCPluginCfgOutputPath_<definitionID>=/path/file_name.txt

   Location in which the plugin-cfg.xml file is placed after the file is generated. Because we can generate the plug-in configuration on any node in the cell, you must ensure the output directory exists on each node.

   ODCPluginCfgUpdateScript_<definitionID>=/path/script <parameter1> <parameter2>

   This property defines the absolute path to the script and the arguments to be passed to the defined script. The defined script will be invoked each time a plugin-cfg.xml is generated.

   (V8502) ODCPluginCfgOdrClusterList_<definitionID>=cell1:cluster1,cell1:cluster2,cell1:*,[cell1:cluster3],[cell1:cluster4]

   This property specifies a cluster of ODRs to include in the plugin-cfg.xml file. Use the asterisk (*) symbol as a valid wildcard for each path segment.cluster1 and cluster2 are marked as primary servers. cluster3 and cluster4 are marked as backup servers.

   ODCPluginCfgDisabled_<definitionID>

   This property disables the generation of a particular configuration without disabling all the properties for that configuration. The default value is false.

   ODCPluginCfgOdrSessionIdCookie_<definitionID>

   Name of the cookie used to maintain IBM HTTP server/ODR affinity when using ODR cell affinity.

   ODCPluginCfgIHSConfigProperties_<definitionID>

   This property is used instead of configuring JVM properties (as is done during non-HA plugin-cfg.xml generation) to set IBM HTTP server specific configuration properties. The value of this property is a comma separated list of ATTRIBUTE_NAME=value pairs where ATTRIBUTE_NAME is the name of an attribute represented in the plugin-cfg.xml.

   For example, if a configuration name of 1 is being used, a cell property named ODCPluginCfgIHSConfigProperties_1 with a value of TrustedProxyEnable=true,LogLevel=INFO,CloneSeparatorChange=true,ServerIOTimeout=60 would be created to set the TrustedProxyEnable, LogeLevel, CloneSeparatorChange, and ServerIOTimeout attributes contained in the generated plugin-cfg.xml.

   ODCPluginCfgTrustedProxyList_<definitionID>=trustedproxy1,trustedproxy2

   Specify the trusted proxies to include in the plugin-cfg.xml file.

   See Controlling the generation of the plugin-cfg.xml file for the list of valid property names and values.

Set the following cell custom properties to generate the plug-in configuration for a collection of ODRs that are not in an ODR cluster. Note that all properties end with _1, which ties them together into a single configuration.

properties used to generate a plug-in configuration for ODRs that

Property name	Property value	Description
ODCPluginCfgOdrList_1	myCell:*:*	Generates a plug-in configuration that will route to all ODRs in the myCell cell.
ODCPluginCfgOutputPath_1	/tmp/plugin-cfg1.xml	Writes the generated plug-in configuration to the /tmp/plugin-cfg1.xml file.
ODCPluginCfgUpdateScript_1	/root/bin/pluginCfgUpdate1	The path to the script that will be invoked each time the /tmp/plugin-cfg1.xml file is updated.

Set the following custom properties to generate the plug-in configuration for a cluster of ODRs named myCell/myOdrCluster. Note that all properties end with _2, which ties them together into a single configuration.

Property name	Property value	Description
ODCPluginCfgOdrClusterList_2	myCell:myOdrCluster	Generates a plug-in configuration that will route to all ODRs of the myOdrCluster cluster in the myCell cell.
ODCPluginCfgOutputPath_2	/tmp/plugin-cfg2.xml	Writes the generated plug-in configuration to the /tmp/plugin-cfg2.xml file.
ODCPluginCfgUpdateScript_2	/root/bin/pluginCfgUpdate2	The path to the script that is ran each time the /tmp/plugin-cfg2.xml file is updated.
ODCPluginCfgOdrIncludeStopped_2	true or false	Includes or excludes stopped ODRs.

What to do next

Because the generation of the plugin-cfg.xml file can occur on any node in the cell, we can determine the specific location in which the generation service is running:

In the console, click Runtime operations > Component stability > Core components. Verify that HAPluginCfgGenerator is displayed in the table.

Related concepts

Overview of request flow prioritization

Related tasks

Segregating HTTP traffic by ODR clusters

Configure an ODR to dynamically update the web server plug-in configuration

Intelligent Management: controlling the generation of the plugin-cfg.xml file

Related information:

Set up a high availability environment