Web server plug-in properties
View or change the settings of a web server plug-in configuration file. The plug-in configuration file, plugin_cfg.xml, provides properties for establishing communication between the Web server and the Application Server.
From the admin console, click...
Servers > Server Types > Web servers > web_server > Plug-in Properties
On the Configuration tab, we can edit fields. On the Runtime tab, we can look at read-only information.
The Runtime tab is available only when this web server has accessed applications running on application servers and there is an http_plugin.log file.
Ignore DNS failures during web server startup
This field corresponds to the IgnoreDNSFailures element in the plugin-cfg.xml file.
When we set the value to true, the plug-in ignores DNS failures within a configuration and starts successfully if at least one server in each ServerCluster is able to resolve the host name. If a server host name cannot be resolved, it is marked unavailable for the continued existence of the configuration. Further attempts to resolve the host name are not made during the routing of requests. If a DNS failure occurs, a message is written to the plug-in log file and the plug-in initialization process continues.
By default, when the value is false, DNS failures cause the plug-in to not initialize and requests fail. However, the web server starts.
Information Value Data type String Default false Refresh configuration interval
Time interval, in seconds, at which the plug-in should check the configuration file to see if updates or changes have occurred. The plug-in checks the file for any modifications that have occurred since the last time the plug-in configuration was loaded.
In a development environment in which changes are frequent, a lower setting than the default setting of 60 seconds is preferable. In production, a higher value than the default is preferable because updates to the configuration will not occur so often. If the plug-in reload fails for some reason, a message is written to the plug-in log file and the previous configuration is used until the plug-in configuration file successfully reloads. If we are not seeing the changes we made to your plug-in configuration, check the plug-in log file for indications of the problem.
Information Value Data type Integer Default 60 seconds. Plug-in configuration file name
File name of the configuration file for the plug-in. The Application Server generates the plugin-cfg.xml file by default. The configuration file identifies applications, Application Servers, clusters, and HTTP ports for the web server. The web server uses the file to access deployed applications on various Application Servers.
This field is disabled and cannot be changed, but the value is displayed for information purposes only.
If a different location is desired, we need to rerun the Plug-in Configuration Tool (pct) to define the new location, and then run the new configureWebserver script that is produced from the install process on our WAS machine.
If we select a web server plug-in during installation, the installer program configures the web server to identify the location of the plugin-cfg.xml file, if possible. The plug-in configuration file, by default, is installed in the plugins_root/config/web_server directory.
The installer program adds a directive to the web server configuration that specifies the location of the plugin-cfg.xml file.
For remote web servers, we must copy the file from the local directory where the Application Server is installed to the remote machine. This is known as propagating the plug-in configuration file. If we are using IBM HTTP Server V6.1 or higher for the web server, WebSphere Application Server can automatically propagate the plug-in configuration file for you to remote machines provided there is a working HTTP transport mechanism to propagate the file.
We can click View to display a copy of the current plug-in configuration file.
Information Value Data type String Default plugin-cfg.xml Automatically generate plug-in configuration file
To automatically generate a plug-in configuration file to a remote web server:
- This field must be checked.
- The plug-in configuration service must be enabled
When the plug-in configuration service is enabled, a plug-in configuration file is automatically generated for a web server whenever:
- The WAS administrator defines new web server.
- An application is deployed to an Application Server.
- An application is uninstalled.
- A virtual host definition is updated and saved.
By default, this field is checked. Clear the check box to manually generate a plug-in configuration file for this web server.
(Dist) Important: When the plug-in configuration file is generated, it does not include admin_host on the list of virtual hosts. The Information Center article, Allowing web servers to access the administrative console, describes how to add admin_host to the list of virtual hosts.
Automatically propagate plug-in configuration file
Automatically propagate a copy of a changed plug-in configuration file to a Web server:
- This field must be checked.
- The plug-in configuration service must be enabled
- In a Network Deployment environment, a WAS node agent must be on the node that hosts the web server associated with the changed plug-in configuration file.
By default, this field is checked.
The plug-in configuration file can only be automatically propagated to a remote web server if that web server is an IBM HTTP Server V6.1 or higher web server and its administration server is running.
Because the plug-in configuration service runs in the background and is not tied to the administrative console, the administrative console cannot show the results of the automatic propagation.
(Dist) For distributed platforms, we can check the related messages in the deployment manager SystemOut.log file to verify that the automatic propagation successfully completed.
(ZOS) For the z/OS platform, we can check the related messages in the TSO JOB log to verify that the automatic propagation successfully completed.
Plug-in key store file name
Fully qualified directory path and file name of the database file containing our security key rings that the Web server plug-in uses for HTTPS requests. This file resides on the Web server associated with this web server plug-in. After we specify the fully qualified directory path and file name of the database file, we can:
- Cick Manage keys and certificates to update this file.
- Click Copy to web server key store directory to add a copy of this file to the key store directory for the web server.
Information Value Data type String Default None Plug-in configuration directory and file name
Fully qualified path of the web server copy of the web server plug-in configuration file. This path is the name of the file and its location on the machine where the web server is running.
This field is disabled and cannot be changed, but the value is displayed for information purposes only.
Plug-in key store directory and file name
Fully qualified path of the web server copy of the database file containing our security key rings. This path is the name of the file and its location on the machine where the web server is running.
This field is disabled and cannot be changed, but the value is displayed for information purposes only.
Plug-in logging
Location and name of the http_plugin.log file. Also specifies the scope of messages in the log.
The log describes the location and level of log messages that are written by the plug-in. If a log is not specified within the configuration file, then, in some cases, log messages are written to the web server error log.
On a distributed platform, if the log file does not exist then it will be created. If the log file already exists, it will be opened in append mode and the previous plug-in log messages will remain.
Log file name: The fully qualified path to the log file to which the plug-in will write error messages.
Information Value Data type String Default plugins_root/logs/web_server/http_plugin.log Specify the file path of the http_plugin.log file.
Log level: The level of detail of the log messages that the plug-in should write to the log. Specify one of the following for this attribute:
Trace All of the steps in the request process are logged in detail. Stats The server selected for each request and other load balancing information relating to request handling is logged. Warn All warning and error messages resulting from abnormal request processing are logged. Error Only error messages resulting from abnormal request processing are logged. Debug All of the critical steps performed in processing requests are logged. Detail All of the information about requests and responses are logged.
If a Log level is not specified, the default value Error is used.
Be careful when setting the level to Trace. A lot of messages are logged at this level which can cause the disk space/file system to fill up very quickly. A Trace setting should never be used in a normally functioning environment as it adversely affects performance.
If the web server and web server plug-in are running on an AIX, HP-UX, Linux, or Solaris system, and we change the log level, in the plugin-cfg.xml file, this change is not picked up dynamically. We must restart the web server to pick up the change. For example on Solaris, if we do not restart the web server, the following error message appears in the Plugin_Home/logs/http_plugin.log file:
ERROR: ws_config_parser:handleLogEnd: Failed to open log file '/opt/IBM/WebSphere/Plugin/logs/sunwebserver/http_plugin.log', OS
Information Value Data type String Default Error
Implement a web server plug-in Use High Performance Extensible Logging to troubleshoot applications Web server plug-in request and response optimization properties Web server plug-in caching properties Web server plug-in request routing properties