plugin-cfg.xml file


 

+

Search Tips   |   Advanced Search

 

Application-centric plugin-cfg.xml files are hosted on the web server and map web server and appserver definitions. Changes made to plugin-cfg.xml using the admin console persist to the plugin-cfg.xml file on the web server upon generation.

Topology-centric files map everything defined in the environment. Typically, this type of plugin-cfg.xml is used when you do not have Web servers defined. If the topology-centric plugin-cfg.xml file exists within...

[WAS_HOME]/dmgr/cells

...the plugin generation process ignores the updated values from admin console...

Application Server | Web Server Plugin Properties

...and uses the existing values within the XML file. In this case, we need to manually update the XML file to have those values to persist.

If the plugin-cfg.xml file does not exist within...

[WAS_HOME]\dmgr\cells

...the plugin generation process creates a new plugin-cfg.xml file. The process persists the latest values that are set on...

Application Server | Web Server Plugin Properties

The design of this file and its related function enable WAS ND to support different types of configurations. For example, Web server definitions might not exist. In addition, many Web server plug-in properties, such as RefreshInterval, LogLevel, and the Edge Side Include (ESI) processor properties, only can be updated manually. Those values must be maintained through each iteration.

The plugin-cfg.xml file includes the following elements and attributes. Unless indicated otherwise, each element and attribute can only be specified once within the plugin-cfg.xml file.

Avoid trouble:

Use the admin console to set these properties for a given Web server definition. Any manual changes you make to the plug-in configuration file for a given Web server are overridden whenever the file is regenerated.

 

Config (required)

This element starts the WebSphere HTTP plug-in configuration file. It can include one or more of the following elements and attributes.

IgnoreDNSFailures

Whether the plug-in ignores DNS failures within a configuration when starting. When set 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. Any server for which the host name can not be resolved is marked unavailable for the life of the configuration. No attempts to resolve the host name are made later on during the routing of requests. If a DNS failure occurs, a log message is written to the plug-in log file and the plug-in initialization continues rather than causing the Web server not to start. The default value is false, meaning DNS failures cause the Web server not to start.

RefreshInterval

The 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 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 not seeing the changes you made to the plug-in configuration, check the plug-in log file for indications of the problem.

ASDisableNagle

Whether the user wants to disable nagle algorithm for the connection between the plug-in and the appserver. By default, nagle algorithm is enabled.

The value can be true or false.

IISDisableNagle

Whether the user wants to disable nagle algorithm on Microsoft Internet Informations Services (IIS). By default, nagle algorithm is enabled.

The value can be true or false.

VHostMatchingCompat (zero or one attribute for each Config)

The port number is to be used for virtual host matching.

  • true if matching is to be done physically by using the port number for which the request was received.
  • false if matching is to be done logically using the port number contained in the host header.

The default is false.

AppServerPortPreference

Port number the appserver should use to build URI's for a sendRedirect.

  • hostHeader if the port number from the host header of the HTTP request coming in is to be used.
  • webserverPort if the port number on which the Web server received the request is to be used.

The default is hostHeader.

ResponseChunkSize

The plug-in reads the response body in 64k chunks until all of the response data is read. This approach causes a performance problem for requests whose response body contains large amounts of data.

The ResponseChunkSize attribute lets specify the maximum chunk size to use when reading the response body. For example, Config ResponseChunkSize="N">, where N equals the chunk size in kilobytes.

If the content length of the response body is unknown, a buffer size of N kilobytes is allocated and the body is read in N kilobyte size chunks, until the entire body is read. If the content length is known, then a buffer size of either content length or N (whichever is less) is used to read the response body.

The default chunk size is 64k.

AcceptAllContent

Whether or not users can include content in POST, PUT, GET, and HEAD requests when a Content-Length or Transfer-encoding header is contained in the request header. We can specify one of the following values for this attribute:

  • True if content is to be expected and read for all requests

  • False if content only is only to be expected and read for POST and PUT requests.

False is the default.

ChunkedResponse

Whether the plug-in should chunk the response to the client when a Transfer-Encoding : Chunked response header is present in the response.

Applies to the IIS, IPlanet, and Domino Web servers. The IBM HTTP Server automatically handles the chunking of the response to the client.

Specify one of the following values for this attribute:

  • true if the plug-in is to chunk the response to the client when a Transfer-Encoding : Chunked response header is present in the response.

  • false if the response is not to be chunked.

false is the default.

IISPluginPriority

Priority in which the IIS Web server loads the WebSphere Web server plug-in. We can specify one of the following values for this attribute:

  • High
  • Medium
  • Low

The default value is High.

NOTES:

  • The IIS Web server uses this value during startup. Therefore, the Web server must be restarted before this change will take effect.

  • The default value of High ensures that all requests are handled by the WebSphere Web server plug-in before they are handled by any other filter/extensions. If problems occur while using a priority of Medium or Low, you will have to rearrange the order or change the priority of the interfering filter/extension.

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.

For example, we might specify the following:

<Log LogLevel="Error" Name="/opt/WebSphere/AppServer60/logs/http_plugin.log"/>

Name (exactly one attribute for each Log)

The fully qualified path to the log file to which the plug-in will write error messages.

If the file does not exist then it will be created. If the file already exists then it will be opened in append mode and the previous plug-in log messages will remain.

LogLevel (zero or one attribute for each Log)

The level of detail of the log messages that the plug-in should write to the log. We can specify one of the following values 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 LogLevel is not specified for the Log element, 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 to fill up very quickly. A Trace setting should never be used in a normally functioning environment as it adversely affects performance.

Property Name="esiEnable" Value="true/false"

Used to enable or disable the Edge Side Include (ESI) processor. If the ESI processor is disabled, the other ESI elements in this file are ignored.

Value can be set to true or false. By default, the ESI processor is enabled (set to true).

Property Name="esiMaxCacheSize" Value="interger"

An integer specifying, in 1K byte units, the maximum size of the cache. The default maximum size of the cache is 1024K bytes (1 megabyte). If the cache is full, the first entry to be evicted from the cache is the entry that is closest its expiration time.

Property Name="ESIInvalidationMonitor" Value="true/false"

Used to indicate whether or not the ESI processor should receive invalidations from the appserver.

Value can be set to true or false. By default, this property is set to false.

Property Name="FIPSEnable" Value="true/false"

Used to indicate whether or not the FIPS is enabled for making secure (SSL) connections to the appserver. This property should be set to true, if FIPS is enabled on the appserver..

Value can be set to true or false. By default, this property is set to false.

ServerCluster (one or more elements for each Config)

A group of servers that are generally configured to service the same types of requests.

In the simplest case, the cluster contains only one server definition. In the case in which more than one server is defined, the plug-in will load balance across the defined servers using either a Round Robin or a Random algorithm. The default is Round Robin.

Following is an example of a ServerCluster element 

<ServerCluster Name="Servers">
    <ClusterAddress Name="ClusterAddr">
        <Transport Hostname="192.168.1.2" Port="9082" Protocol="HTTP"/>
        <Transport Hostname="192.168.1.2" Port="9443" Protocol="HTTPS">
            <Property Name="Keyring" value="c:/WebSphere/AppServer/keys/keyring.kdb"/>
            <Property Name="Stashfile" value="c:/WebSphere/AppServer/keys/keyring.sth"/>
        </Transport>
    </ClusterAddress>
    <Server Name="Server1">
        <Transport Hostname="192.168.1.3" Port="9082" Protocol="HTTP"/>
        <Transport Hostname="192.168.1.3" Port="9443" Protocol="HTTPS">
            <Property Name="Keyring" value="c:/WebSphere/AppServer/keys/keyring.kdb"/>
            <Property Name="Stashfile" value="c:/WebSphere/AppServer/keys/keyring.sth"/>
        </Transport>
    </Server>
    <Server Name="Server2">
        <Transport Hostname="192.168.1.4" Port="9082" Protocol="HTTP"/>
        <Transport Hostname="192.168.1.4" Port="9443" Protocol="HTTPS">
            <Property Name="Keyring" value="c:/WebSphere/AppServer/keys/keyring.kdb"/>
            <Property Name="Stashfile" value="c:/WebSphere/AppServer/keys/keyring.sth"/>
        </Transport>
    </Server>
    <Server Name="Server3">
        <Transport Hostname="192.168.1.5" Port="9082" Protocol="HTTP"/>
        <Transport Hostname="192.168.1.5" Port="9443" Protocol="HTTPS">
            <Property Name="Keyring" value="c:/WebSphere/AppServer/keys/keyring.kdb"/>
            <Property Name="Stashfile" value="c:/WebSphere/AppServer/keys/keyring.sth"/>
        </Transport>
    </Server>
    <PrimaryServers>
        <Server Name="Server1"/>
        <Server Name="Server2"/>
    </PrimaryServers>
    <BackupServers>
        <Server Name="Server3"/>
    </BackupServers>
</ServerCluster>

Name (exactly one attribute for each ServerCluster)

The logical or admin name to be used for this group of servers.

LoadBalance (zero or one attribute for each ServerCluster)

The default load balancing type is Round Robin.

The Round Robin implementation has a random starting point. The first server will be picked randomly. Round Robin will be used to pick servers from that point forward. This implementation ensures that in multiple process based Web servers, all of the processes don't start up by sending the first request to the same Application Server.

IgnoreAffinityRequests (zero or one attribute for each ServerCluster)

Whether the plug-in ignores the number of affinity requests made to a server when selecting servers based on the Round Robin algorithm. The value can be true or false. If the value is set to false, the number of affinity requests made is also taken into account in the server selection process.

The default value is true, which means the number of affinity requests made are not used in the Round Robin algorithm.

RetryInterval (zero or one attribute for each ServerCluster)

An integer specifying the length of time that should elapse from the time that a server is marked down to the time that the plug-in will retry a connection. The default is 60 seconds.

RemoveSpecialHeaders (zero or one attribute for each ServerCluster)

The plug-in adds special headers to the request before it is forwarded to the appserver. These headers store information about the request that will need to be used by the application. By default the plug-in will remove these headers from incoming requests before adding the headers it is supposed to add.

The value can be true or false. Setting the attribute to false introduces a potential security exposure by not removing headers from incoming requests.

CloneSeparatorChange (zero or one attribute for each ServerCluster)

Some pervasive devices cannot handle the colon character (:) used to separate clone IDs in conjunction with session affinity. This attribute for the server group tells the plug-in to expect the plus character (+) as the clone separator. You must change appserver configurations so that an appserver separates clone IDs with the plus character as well.

The value can be true or false.

PostSizeLimit (zero or one attribute for each ServerCluster)

The maximum number of bytes of request content allowed in order for the plug-in to attempt to send the request to an appserver. If a request is received that is greater than this size, the plug-in fails the request. The default value is -1 bytes, which indicates that there is no limit for the post size.

PostBufferSize (zero or one attribute for each ServerCluster)

Specifies, in kilobytes, the maximum buffer size used when the content of an HTTP request is read. If the appserver that initially receives a request cannot process that request, the data contained in this buffer is sent to another appserver in an attempt to have that appserver process the request.

This option improves the availability of the plug-in. The requests in flight having content are now retried if the selected application server is not responding. If the value is set to zero, the requests having content are not buffered and are not retried. The default value is 64.

Server (one or more elements for each ServerCluster)

A WAS instance configured to handle requests routed to it given the routing rules of the plug-in configuration. The Server should correspond to an appserver running on either the local machine or a remote machine.

Name (exactly one attribute for each Server)

The admin or logical name for the server.

CloneID (zero or one attribute for each Server)

If this unique ID is present in the HTTP cookie header of a request (or the URL if using URL rewriting), the plug-in routes the request to this particular server, provided all other routing rules are met. If a CloneID is not specified in the Server, then session affinity is not enabled for this server.

This attribute is used in conjunction with session affinity. When this attribute is set, the plug-in checks the incoming cookie header or URL for JSESSIONID. If JSESSIONID is found then the plug-in looks for one or more clone IDs. If clone IDs are found, and a match is made to the value specified for this attribute, then the request is sent to this server rather than load balanced across the cluster.

If not using session affinity then it is best to remove these clone IDs from the configuration because there is added request processing in the plug-in when these are set. If clone IDs are not in the plug-in then it is assumed that session affinity is not on and the request is load balanced across the cluster.

WaitForContinue (zero or one attribute for each Server)

Whether to use the HTTP 1.1 100 Continue support before sending the request content to the appserver. Possible attribute values are true or false. The default value is false; the plug-in does not wait for the 100 Continue response from the appserver before sending the request content because it is a performance hit.

This property will be ignored for POST requests in order to prevent a failure from occurring if the Application Server closes a connection because of a keep alive time-out.

Enable this function (set to true) when configuring the plug-in to work with certain types of proxy firewalls.

LoadBalanceWeight (zero or one attribute for each Server)

Weight associated with this server when the plug-in does weighted Round Robin load balancing. The starting value for a server can be any integer between 0 and 20. However, zero should be specified only for a server that is shut down.

The LoadBalanceWeight for each server is decremented for each request processed by that server. After the weight for a particular server in a server cluster reaches zero, only requests with session affinity are routed to that server. When all servers in the cluster reach a weight of zero, the weights for all servers in the cluster are reset, and the algorithm starts over.

When a server is shut down, it is recommended set the weight for that server to zero. The plug-in can then reset the weights of the servers that are still running, and maintain proper load balancing.

ConnectTimeout (zero or one attribute for each Server)

The ConnectTimeout attribute of a Server element enables the plug-in to perform non-blocking connections with the appserver. Non-blocking connections are beneficial when the plug-in is unable to contact the destination to determine if the port is available or unavailable.

If no ConnectTimeout value is specified, the plug-in performs a blocking connect in which the plug-in sits until an operating system times out (as long as two minutes depending on the platform) and allows the plug-in to mark the server unavailable. A value of 0 causes the plug-in to perform a blocking connect. A value greater than 0 specifies the number of seconds you want the plug-in to wait for a successful connection. If a connection does not occur after that time interval, the plug-in marks the server unavailable and fails over to one of the other servers defined in the cluster. The default value is 5 seconds.

ExtendedHandshake (zero or one attribute for each Server)

The ExtendedHandshake attribute is used when a proxy firewall is between the plug-in and the appserver. In such a case, the plug-in is not failing over, as expected.

The plug-in marks a server as down when the connect() fails. However, when a proxy firewall is in between the plug-in and the appserver, the connect() will succeed, even though the back end appserver is down.

This causes the plug-in to not failover correctly to other application servers.

The plug-in performs some handshaking with the application server to ensure that it is started before sending the request. This enables the plug-in to failover in the event the appserver is down.

The value can be true or false.

MaxConnections (one element for each Server)

The MaxConnections attribute is used to specify the maximum number of active connections to an appserver that can be flowing through a Web server process at any point in time. For example, assuming that:

  • The appserver is fronted by 5 nodes that are running an IBM HTTP Server.

  • Each node starts 2 processes.

  • The MaxConnections attribute is set to 50.

In this example, the appserver could potentially get up to 500 connections. (You take the number of nodes, 5, multiply it by the number of processes, 2, and then multiply that number by the number specified for the MaxConnections attribute, 50, for a total of 500 connections.)

By default, MaxConnections is set to -1. If this attribute is set to either zero or -1, there is no limit to the number of pending connections to the appservers.

Transport (one or more elements for each Server)

The transport for reading and writing requests to a particular WebSphere application server instance. The transport provides the information needed to determine the location of the appserver to which the request will be sent. If the Server has multiple transports defined to use the same protocol, the first one will be used.

It is possible to configure the Server to have one non-secure transport and one that uses SSL. In this configuration, a match of the incoming request protocol will be performed to determine the appropriate transport to use to send the request to the appserver.

Hostname (exactly one attribute for each Transport)

The host name or IP address of the machine on which the WebSphere application server instance is running.

Port (exactly one attribute for each Transport)

The port on which the WebSphere application server instance is listening.

Protocol (exactly one attribute for each Transport)

The protocol to use when communicating over this transport -- either HTTP or HTTPS.

Property (zero, one, or more elements for each Transport)

When the Protocol of the Transport is set to HTTPS, use this element to supply the various initialization parameters, such as password, keyring and stashfile. for example, the portion of the plugin_cfg.xml file containing these elements might look like the following: 

<Transport Hostname="192.168.1.2" Port="9443" Protocol="HTTPS">
<Property Name="keyring" value="c:/WebSphere/AppServer/keys/keyring.kdb"/>
<Property Name="stashfile" value="c:/WebSphere/AppServer/keys/keyring.sth"/>
<Property Name="password" value="WebAS"/>

The default password for viewing the plugin-key.kdb file using iKeyMan is WebAS.

Name (exactly one attribute for each Property)

The name of the Property being defined. Supported names recognized by the transport are keyring, stashfile, and password.

Avoid trouble: password is the only name that can be specified for the WebSphere HTTP Plug-in for z/OS. keyring, and stashfile, if specified, will be ignored.

Value (exactly one attribute for each Property)

The value of the Property being defined.

ServerIOTimeout

The ServerIOTimeout attribute of a server element enables the plug-in to set a time out value, in seconds, for sending requests to and reading responses from the appserver. If a value is not set for the ServerIOTimeout attribute, the plug-in, by default, uses blocked I/O to write request to and read response from the application server until the TCP connection times out. For example, if we specify:

<Server Name="server1" ServerIOTimeout=300>

In this case, if an appserver stops responding to requests, the plug-in waits 300 seconds (5 minutes) before timing out the TCP connection. Setting the ServerIOTimeout attribute to a reasonable value enables the plug-in to time out the connection sooner, and transfer requests to another appserver when possible.

When selecting a value for this attribute, remember that sometimes it might take a couple of minutes for an appserver to process a request. Setting the value of the ServerIOTimeout attribute too low could cause the plug-in to send a false server error response to the client. The default value is 60 seconds.

ClusterAddress (zero or one element for each ServerCluster)

A ClusterAddress is like a Server element in that we can specify the same attributes and elements as for a Server element. The difference is that we can only define one of them within a ServerCluster. Use a ClusterAddress when you do not want the plug-in to perform any type of load balancing because you already have some type of load balancer in between the plug-in and the appserver.

If we include a ClusterAddress tag, include the Name attribute on that tag. The plug-in uses the name attribute to associate the cluster address with the correct host and port. If we do not specify the Name attribute, the plug-in assigns the cluster address the name specified for the server using the same host and port. 

<ClusterAddress Name="MyClusterAddr">
<Transport Hostname="192.168.1.2" Port="9082" Protocol="HTTP"/>
<Transport Hostname="192.168.1.2" Port="9443" Protocol="HTTPS">
</ClusterAddress>

If a request comes in that does not have affinity established, the plug-in routes it to the cluster address, if defined. If affinity has been established, then the plug-in routes the request directly to the clone, bypassing the cluster address entirely. If no cluster address is defined for the server cluster, then the plug-in load balances across the servers in the primary servers list.

PrimaryServers (zero or one element for each server cluster)

List of servers to which the plug-in routes requests for this cluster. If a list of primary servers is not specified, the plug-in routes requests to servers defined for the server cluster.

BackupServers (zero or one element for each server cluster)

List of servers to which requests should be sent to if all servers specified in the primary servers list are unavailable. The plug-in does not load balance across the backup servers, but traverses the list in order until no servers are left in the list or until a request is successfully sent and a response received from an application server.

VirtualHostGroup

A group of virtual host names that will be specified in the HTTP Host header. Enables you to group virtual host definitions together that are configured to handle similar types of requests.

Following is an example of a VirtualHost Group element and associated elements and attributes 

<VirtualHostGroup Name="Hosts">
<VirtualHost Name="www.x.com"/>
<VirtualHost Name="www.x.com:443"/>
<VirtualHost Name="*:8080"/>
<VirtualHost Name="www.x.com:*"/>
<VirtualHost Name="*:*"/>
</VirtualHostGroup>

Name (exactly one attribute for each VirtualHostGroup)

The logical or admin name to be used for this group of virtual hosts.

VirtualHost (one or more elements for each VirtualHostGroup)

The name used for a virtual or real machine used to determine if incoming requests should be handled by WAS or not. Use this element to specify host names that will be in the HTTP Host header which should be seen for requests that need to be handled by the appserver. We can specify specific host names and ports that incoming requests will have or specify an asterisk (*) for either the host name, port, or both.

Name (exactly one attribute for each VirtualHost)

The actual name that should be specified in the HTTP Host header in order to match successfully with this VirtualHost.

The value is a host name or IP address and port combination, separated by a colon.

Configure the plug-in to route requests to the appserver based on the incoming HTTP Host header and port for the request. The Name attribute specifies what those combinations are.

Use a wildcard for this attribute. The only acceptable solutions are either an asterisk (*) for the host name, an asterisk for the port, or an asterisk for both. An asterisk for both means that any request will match this rule. If no port is specified in the definition the default HTTP port of 80 is assumed.

UriGroup

A group of URIs that will be specified on the HTTP request line. The same appserver must be able to handle the URIs. The route will compare the incoming URI with the URIs in the group to determine if the appserver will handle the request.

Following is an example of a UriGroup element and associated elements and attributes: 

<UriGroup Name="Uris">
<Uri Name="/servlet/snoop"/>
<Uri Name="/webapp/*"/>
<Uri Name="*.jsp"/>
</UriGroup>

Name (exactly one attribute for each UriGroup)

The logical or admin name for this group of URIs.

Uri (one or more elements for each UriGroup)

The virtual path to the resource that will be serviced by WAS. Each URI specifies the incoming URLs that need to be handled by the appserver. Use a wildcard in these definitions.

Name (exactly one attribute for each Uri)

The actual string that should be specified in the HTTP request line in order to match successfully with this URI. Use a wildcard within the URI definition. We can specify rules such as *.jsp or /servlet/* to be handled by WAS. When you assemble the application, if we specify File Serving Enabled then only a wildcard URI is generated for the Web app, regardless of any explicit servlet mappings. If we specify Serve servlets by classname then a URI having...

<Uri Name="Web_application_URI/servlet/*">

...is generated.

AffinityCookie (zero or one attribute for each Uri)

The name of the cookie the plug-in should use when trying to determine if the inbound request has session affinity. The default value is JSESSIONID.

See the description of the CloneID attribute for additional session affinity information.

AffinityURLIdentifier (zero or one attribute for each Uri)

The name of the identifier the plug-in should use when trying to determine if the inbound request has affinity specified in the URL to a particular clone. The default value is jsessionid.

See the description of the CloneID attribute for additional session affinity information.

Route

A request routing rule by which the plug-in will determine if an incoming request should be handled by a WebSphere application server.

The route definition is the central element of the plug-in configuration. It specifies how the plug-in will handle requests based on certain characteristics of the request. The route definition contains the other main elements: a required ServerCluster, and either a VirtualHostGroup, UriGroup, or both.

Use the information that is defined in the VirtualHostGroup and the UriGroup for the route, the plug-in determines if the incoming request to the Web server should be sent on to the ServerCluster defined in this route.

Following is an example of this element: 

<Route VirtualHostGroup="Hosts" UriGroup="Uris" ServerCluster="servers/>

VirtualHostGroup (zero or one attribute for each Route)

The group of virtual hosts that should be used in route determination. The incoming host header and server port are matched to determine if this request should be handled by the appserver.

It is possible to omit this from the route definition. If it is not present then every request will match during the virtual host match portion of route determination.

UriGroup (zero or one attribute for each Route)

The group of URIs to use for determining the route. The incoming URI for the request is matched to the defined URIs in this group to determine if this request should be handled by the application server.

It is possible to omit this from the route definition. If it is not present than every request will match during the URI match portion of route determination.

ServerCluster (exactly one attribute for each Route)

The cluster to which to send request that successfully match the route.

The cluster that should be used to handle this request. If both the URI and the virtual host matching is successful for this route then the request is sent to one of the servers defined within this cluster.

RequestMetrics

This element is used to determine if request metrics is enabled, and how to filter the requests based on the Internet protocol (IP) and Uniform Resource Identifiers (URI) filters when request metrics is enabled.

Following is an example of this element: 

<RequestMetrics armEnabled="false"  loggingEnabled="true"
      rmEnabled="false" traceLevel="PERF_DEBUG">

armEnabled (zero or one attribute for RequestMetrics)

This attribute indicates whether the ARM 4 agent is enabled in the plug-in. When it is set to true, the ARM 4 agent will be called.

For the SunOne (iPlanet) Web server the following directive must be included in the obj.conf file to enable ARM 4 support:

AddLog fn="as_term"

If this directive is not included, the arm_stop procedure will never be called.

loggingEnabled (exactly one attribute for RequestMetrics)

This attribute indicates whether request metrics logging is enabled in the plug-in. When it is set to true and the traceLevel is not set to NONE, the request response time (and other request information) is logged. When it is set to false, there is no request logging. The value of loggingEnabled depends on the value specified for the system property com.ibm.websphere.pmi.reqmetrics.loggingEnabled. When this system property is not present, loggingEnable is set to true.

rmEnabled (exactly one attribute for RequestMetrics)

This attribute indicates whether or not the request metrics is enabled in the plug-in. When it is set to true, the plug-in request metrics will look at the filters and log the request trace record in the plug-in log file. This action is performed if a request passes the filters. When this attribute is set to false, the rest of the request metrics attributes will be ignored..

traceLevel (exactly one attribute for RequestMetrics)

When rmEnabled is true, this attribute indicates how much information is logged. When this attribute is set to NONE, no request logging is performed. When this attribute is not set to NONE, and loggingEnabled is set to true, the request response time (and other request information) is logged when the request is done.

filters (zero, one, or two attributes for RequestMetrics)

When rmEnabled is true, the filters control which requests are traced.

enable (exactly one attribute for each filter)

When enable is true, the type of filter is on and requests must pass the filter.

type (exactly one attribute for each filter)

There are two types of filters: SOURCE_IP (for example, client IP address) and URI. For the SOURCE_IP filter type, requests are filtered based on a known IP address. We can specify a mask for an IP address using the asterisk (*). If the asterisk is used, the asterisk must always be the last character of the mask, for example 127.0.0.*, 127.0.*, 127*. For performance reasons, the pattern matches character by character, until either an asterisk is found in the filter, a mismatch occurs, or the filters are found as an exact match.

For the URI filter type, requests are filtered based on the URI of the incoming HTTP request. The rules for pattern matching are the same as matching SOURCE_IP address filters.

If both URI and client IP address filters are enabled, Request Metrics requires a match for both filter types. If neither is enabled, all requests are considered a match.

filterValues (one or multiple attribute for each filter)

The filterValues show the detailed filter information.

value (exactly one attribute for each filterValue)

Filter value for the corresponding filter type. This could be either a client IP address or a URI.

enableESIToPassCookies

Whether to allow forwarding of session cookies to WAS when processing ESI include requests. If the value is set to true, this custom property is enabled. If the value is set to false, the custom property is disabled. By default, the value is set to false.

GetDWLMTable

Whether to allow a newly spawned plug-in process to proactively request a partition table from WAS before it handles any HTTP requests. This custom property is used only when memory-to-memory session management is configured. If the value is set to true, this custom property is enabled. If the value is set to false, the custom property is disabled. By default, the value is set to false.



 

Related tasks


Communicating with Web servers