# Server Configuration Reference

## The JK 2 Connector

Introduction

> The JK 2 Connector element represents a Connector component that communicates with a web connector via the `AJP` protocol. This is used for cases where you wish to invisibly integrate Tomcat 4 into an existing (or new) Apache installation, and you want Apache to handle the static content contained in the web application, and/or utilize Apache's SSL processing. In many application environments, this will result in better overall performance than running your applications under Tomcat stand-alone using the HTTP/1.1 Connector. However, the only way to know for sure whether it will provide better performance for your application is to try it both ways.

> This connector supports load balancing when used in conjunction with the `jvmRoute` attribute of the Engine.

Attributes

> Common Attributes

> > All implementations of Connector support the following attributes:

> > Attribute | Description
> > --- | ---
> > `className` | Java class name of the implementation to use. This class must implement the `org.apache.catalina.Connector` interface. You must specify the standard value defined below.
> > `enableLookups` | Set to `true` if you want calls to `request.getRemoteHost()` to perform DNS lookups in order to return the actual host name of the remote client. Set to `false` to skip the DNS lookup and return the IP address in String form instead (thereby improving performance). By default, DNS lookups are disabled.
> > `redirectPort` | If this Connector is supporting non-SSL requests, and a request is received for which a matching `<security-constraint>` requires SSL transport, Catalina will automatically redirect the request to the port number specified here.
> > `scheme` | Set this attribute to the name of the protocol you wish to have returned by calls to `request.getScheme()`. For example, you would set this attribute to "`https`" for an SSL Connector. The default value is "`http`".
> > `secure` | Set this attribute to `true` if you wish to have calls to `request.isSecure()` to return `true` for requests received by this Connector (you would want this on an SSL Connector). The default value is `false`.
> > `URIEncoding` | This specifies the character encoding used to decode the URI bytes, after %xx decoding the URL. If not specified, ISO-8859-1 will be used.
> > `useBodyEncodingForURI` | This specifies if the encoding specified in contentType should be used for URI query parameters, instead of using the URIEncoding. This setting is present for compatibility with Tomcat 4.1.27 and earlier. The default value is `true`.

> Standard Implementation

> > The standard implementation of JK 2 Connector is org.apache.coyote.tomcat4.CoyoteConnector, but you must specify the protocolHandlerClassName attribute (see below).

> > This implementation supports the AJP/1.3 protocol.

> > It supports the following additional attributes (in addition to the common attributes listed above):

> > Attribute | Description
> > --- | ---
> > `acceptCount` | The maximum queue length for incoming connection requests when all possible request processing threads are in use. Any requests received when the queue is full will be refused. The default value is 10.
> > `debug` | The debugging detail level of log messages generated by this component, with higher numbers creating more detailed output. If not specified, this attribute is set to zero (0).
> > `maxProcessors` | The maximum number of request processing threads to be created by this Connector, which therefore determines the maximum number of simultaneous requests that can be handled. If not specified, this attribute is set to 20.
> > `minProcessors` | The number of request processing threads that will be created when this Connector is first started. This attribute should be set to a value smaller than that set for `maxProcessors`. The default value is 5.
> > `port` | The TCP port number on which this Connector will create a server socket and await incoming connections. Your operating system will allow only one server application to listen to a particular port number on a particular IP address.
> > `protocolHandlerClassName` | This attribute value must be `org.apache.jk.server.JkCoyoteHandler` to use the JK 2 handler.

Nested Components

Configuration HOWTOs

> Please refer to the Coyote JK 2 documentation for HOWTOs and complete configuration information.

Copyright © 1999-2002, Apache Software Foundation