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 Resin Server | Application Server (Java EE Certified) and Web Server

resin with iis

Resin provides a fast servlet runner for IIS, allowing IIS to run servlets and JSP files.

If you have not yet done so, we suggest you research the Resin standalone web server option first.

Note: isapi_srun.dll should only be used with versions of IIS that do not provide integration with .NET.

Before you integrate Resin with IIS

Starting with version 4.0.7 Resin provides an IIS handler built using ASP.NET technologies. The handler is distributed with Resin in a dll namedResin.IIS.Handler.dll. The dll delivers an implementation of ASP.NET's System.Web.IHttpHandler that facilitates streaming content from Resin via IIS. This can be useful in a number of configurations where the main requirenment is having IIS serving as a front-end to the clients (browsers).

In configurations that don't exhibit the aforementioned requriement a more powerful configuration of homogeneous Resin environment is recommended. Many users find that the performance, flexibility, and features of Resin make Resin a desirable replacement for IIS.

Before integrating Resin with IIS, it is valuable to configure Resin as a standalone server, especially with more complicated setups such as those involving virtual hosts. Doing so isolates the steps and makes troubleshooting easier.

IIS Prerequisites

Resin IIS Handler relies on functionality provided by ASP.NET framework. The handler may also be used with earlier versions of IIS provided that ASP.NET framework is installed with the following Application Development Features enabled:

  • .NET Extensibility
  • ASP
  • ISAPI Extensions
  • ISAPI Filters

It's also recommended that IIS Management Console and IIS Management Scripts and Tools features are enabled. IIS Scripts come with a command line IIS configuration utilityappcmd.exe. Once the feature is installed, appcmd.exe utility will be placed into %SystemRoot%\system32\inetsrv directory. Note: the directory won't be added to %PATH% automatically.

How Resin Integrates with IIS

In the deployment scenarios made available by the IIS Handler, Resin can serve application completely or partially. Capability to serve application partially may be especially useful in scenarios where applicaton uses a mix of .NET and Java technologies. Such situations may arise when porting an application between platforms.

In all deployment schemes Resin IIS Handler needs to be added to the handlers section in ASP.NET web application configuration file located in the root of the context, where the context may be a Site Context or Web Application Context.

The Diagram below depicts a deployment with Resin IIS Handler configured to handle all requests to *.jsp pages, while all static content is served by IIS.

browser <-> (IIS/iis_srun.dll <- html) <-> Resin httpd/servlets,beans <- html,jsp

Next section explains how to install and configure Resin IIS Handler to handle variuos scenarios.

Installing and Configuring Resin IIS Handler

Installing Resin IIS Pugin into IIS requires following the rules defined for ASP.NET extensions, which prescribe location of the binaries and configuration steps including:

  • Copying Resin.IIS.Handler.dll to web application's bin directory
  • Registering the handler in ASP.NET web application config file

The bin directory is located at the root of the context which can be a web site context or a web application context. In both cases bin directory needs to be created if one does not exist already. E.g. after deploying the dll to handle requests at the default web site level the web site context contents tree should looks like the following:


If the permissions don't allow the dll file to be copied into the needed location higher trust level needs to be requested from system's administrator.

Once the dll is copied into the directory it is ready for registering it with the context. Registration can be done manually, by adding a handler to web application context configuration file. The web application configuration file in ASP.NET is named web.config and is placed in the root of the context. E.g. for default site the configuration file will be located in c:\inetpub\wwwroot directory. If the file isn't there it can be created manually or, if appcmd utility is used, automatically.

Successful registration of Resin IIS Handler manually or using appcmd should produce a file that will look as the following simplified but complete configuration file.

<?xml version="1.0" encoding="UTF-8"?>
      <add name="ResinHandlerFactory" <!--Name used by resin handler. Can be changed.-->
           path="*" <!-- Requests path to invoke the handler on-->
           verb="*" <!-- HTTP Method. possible values: 'GET', 'POST', 'HEAD' or combination 'GET,POST' -->
           type="Caucho.IIS.ResinHandlerFactory" <!-- Resin Handler Factory that supplies one reusable handler instance-->
    <add key="resin.servers" value=""/> <!-- Address and port to Resin server(s)-->
    <add key="resin.log-level" value="Information"/> <!-- logging level used by Resin IIS Handler. Use 'None' for silent operation-->

Configuration given above register Resin IIS Handler to handle requests coming at any url by specifying a wild card for path attribute: path="*"

In order to have Resin IIS Handler serve only jsp files the path attribute needs to be given a value of "*.jsp". The values for attributes follow the rules and conventions defined for IIS and are limited in their matching capabilities.

Resin IIS Handler communicates with Resin using HMUX (Resin's internal protocol) with the connection made to the port defined in Resin's configuration file. Matching Resin configuration for the example IIS configuration given above must bind Resin HMUX listener to port 6800.

<resin xmlns=""
  <cluster id="app-tier">
    <server id="" address="" port="6800"/>

Port 6800 is the default HMUX port used by Resin.

Resin IIS Handler accepts the following configuration parameters:

resin.serversSpace separated list of ip:port pairs to backend Resin servers e.g. ''
resin.log-levelLogging level: Information | Warning | Error | None Error
resin.session-cookieSession Cookie NameJSESSIONID
resin.ssl-session-cookieSecure Session Cookie NameSSLJSESSIONID
resin.sticky-sessionsUse sticky sessions for distributing requeststrue
resin.session-url-prefixprefix used to identifiy sessionid in urls;jsessionid=
resin.load-balance-connect-timeoutTimeout used with connect to backend5 sec.
resin.load-balance-idle-timeMaximum time to keep sockets to backend open5 sec.
resin.load-balance-recover-timeRetry period on failed backend server15 sec.
resin.socket-timeoutHow long to wait for a read or write operation to backend server to complete 65 sec.
resin.caucho-statusEnables or disables /caucho-status request. true

In order to configure Resin IIS Handler to communicate to a set of Resin Pro Servers resin.servers configuration parameter needs be an enumeration of ip:port pairs:

<?xml version="1.0" encoding="UTF-8"?>
      <add name="ResinHandlerFactory" <!--Name used by resin handler. Can be changed.-->
           path="*" <!-- Requests path to invoke the handler on-->
           verb="*" <!-- HTTP Method. possible values: 'GET', 'POST', 'HEAD' or combination 'GET,POST' -->
           type="Caucho.IIS.ResinHandlerFactory" <!-- Resin Handler Factory that supplies one reusable handler instance-->
    <add key="resin.servers" value=""/> <!-- Address and port to Resin server(s)-->
    <add key="resin.log-level" value="Information"/> <!-- logging level used by Resin IIS Handler. Use 'None' for silent operation-->

Configuring using appcmd.exe configuration utility

Appcmd.exe offers a command line interface to configuring IIS server. Below are the examples showing how to use the utility to configure various aspects of Resin IIS Handler.

Assuming that we are working with the Default Web Site:

Registering the Resin IIS Handler
        # Remove Resin IIS Hanlder if one is registered
        %APPCMD% set config "Default Web Site" /section:handlers /-[name='ResinHandlerFactory']

        # Add Resin IIS Handler
        %APPCMD% set config "Default Web Site" /section:handlers /+[name='ResinHandlerFactory',path='*',\

        # Note: The above command needs to be issued in one line. The \ character
        # at the last position of the first line is used to denote that command
        # continues on next line

        # Note: %APPCMD% should be pointing to the location of appcmd.exe utility.
        #       default location is c:\Windows\System32\inetsrv\appcmd.exe

Specifying parameters using appcmd.exe:

Resin IIS Hanlder parameters
        # Remove resin.servers parameter
        %APPCMD% set config "Default Web Site" /section:appSettings /-[key='resin.servers']
        # Set resin.servers parameter
        %APPCMD% set config "Default Web Site" /section:appSettings /+[key='resin.servers',value='']

        # Remove resin.log-level parameter
        %APPCMD% set config "Default Web Site" /section:appSettings /-[key='resin.log-level']
        # Set resin.log-level parameter to 'Information'
        %APPCMD% set config "Default Web Site" /section:appSettings /+[key='resin.log-level',value='Information']

Servicing a mixed technologies application

Using Resin IIS Handler it's possible to deploy an application that employes both ASP.NET and JSP technologies. In such a configuration requests for Java EE based resources needs to be forwarded to Resin while the rest can be served by IIS.

E.g. Assuming an applicaiton consists of index.jsp and an index.aspx page in application residing at path c:\temp\a. To be able to serve such an application from both Resin and IIS it needs to be deployed at both.

Deploying application /a to Resin
        <cluster id="app-tier">
          <server id="" port="6800"/>
          <web-app id="/a" root-directory="c:/temp/a"/>

Deploying application '/a' to IIS can be done with IIS Manager, by executing 'Add Applicaton' action from the 'Site's' context menu. Once the 'Add Application' dialog opens field Alias needs to be supplied value of 'a', field Physical path – value of 'c:\temp\a'

Once this configuration is complete copy the Resin.IIS.Handler.dll into the 'c:\temp\a\bin' directory and create web.conf file with settings configured to match '*.jsp' requests and forward them to an instance of Resin.

<?xml version="1.0" encoding="UTF-8"?>
    <add name="ResinHandlerFactory"path="*.jsp"verb="*"type="Caucho.IIS.ResinHandlerFactory"preCondition="integratedMode"/>
  <add key="resin.servers" value=""/>
  <add key="resin.log-level" value="Information"/>

Tracing & Logging with Resin IIS Handler


When Resin IIS Handler is compiled with TRACE option enabled it uses System.Diagnostics.Trace class to output detailed information for every request. This can be useful in debugging errors. Tracing information will go into a file configured in a tracing listener.

Configuring Resin IIS Handler for tracing
<?xml version="1.0" encoding="UTF-8"?>
    <trace autoflush="true" indentsize="0">
         <add name="resin-trace" initializeData="C:\temp\resin-iis-trace.log" type="System.Diagnostics.TextWriterTraceListener" />

Note, that Resin IIS Handler in distribution compiled with no TRACE option.


Resin IIS Handler uses standart .NET loggin mechanism to output information on its opeartion. Upon startup, the handler attempts to initialize Logging to write to 'Application' log using 'Resin IIS Handler' log source. If the log source can not be created automatically due to permissions or other issues, the source can be created manually be adding a key 'Resin IIS Handler' to log sources collection in the registry at

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application\Resin IIS Handler

Alternatively, copy the contents of the following text box into a file with .reg extension and double click on it to import into registry.

Resin IIS Handler Logging Source
Windows Registry Editor Version 5.00

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application\Resin IIS Handler

Starting the app-tier Resin server

Now you need to start the app-tier Resin server. Starting Resin is the same with IIS or standalone. See the Resin Web Server page for a detailed description.

        win> resin.exe console
        Resin 4.0.7 (built Mon Aug 4 09:26:44 PDT 2006)
        Copyright(c) 1998-2006 Caucho Technology. All rights reserved.

        Starting Resin on Mon, 04 Aug 2006 09:43:39 -0700 (PDT)
        [09:43:40.664] Loaded Socket JNI library.
        [09:43:40.664] http listening to *:8080
        [09:43:40.664] ServletServer[] starting
        [09:43:40.879] hmux listening to *:6800
        [09:43:41.073] Host[] starting
        [09:43:41.446] Application[http://localhost:8080/resin-doc] starting
        [09:43:41.496] Application[http://localhost:8080] starting

Resin will print every port it's listening to. In the above example, Resin has an http listener on port 8080 and an server listener on port 6800 (using its custom 'HMUX' protocol). Resin IIS Handler establishes connections to Resin using port 6800, and a web browser can connect using port 8080. Usually the 8080 port will be unused, because web browsers will make requests to IIS, these requests get dispatched to Resin as needed by Resin IIS Handler. A Resin configured http listener on port 8080 is a useful debugging tool, it allows you to bypass IIS and make a request straight to Resin.

Resin IIS Handler Status

caucho-status is optional and probably should be avoided in a production site. It lets you ask the Caucho IIS module about it's configuration, and the status of the backend server(s), valuable for debugging. To see caucho-status point your browser url to http://iisserver/caucho-status.

Note, that in a configuration where handler mapping prevents handler from being invoked on /caucho-status request a 404 will be returned. In such configuration /caucho-status may still be available if there is an extension mapping present for the handler e.g. '*.jsp' or '*.xtp' – simply add the extension to status request http://iisserver/caucho-status.jsp or http://iisserver/cauchos-status.xtp

Copyright © 1998-2012 Caucho Technology, Inc. All rights reserved. Resin ® is a registered trademark. Quercustm, and Hessiantm are trademarks of Caucho Technology.