Connecting Internet Information Server with SAP J2EE Engine 6.20

Connecting Microsoft Internet Information Server (IIS) to SAP J2EE Engine 6.20 extends the functions provided by IIS. From a client viewpoint, the connection with the application server remains invisible, because each request goes to the Web server (IIS) and each response comes from it. The client-server protocol along with the HTTP tunneling mechanism provides access to all resources of the application server, without having direct access to it. This feature provides several benefits:

Improved security – SAP J2EE Engine 6.20 is behind a firewall. For example, all client requests come to IIS.
Greater reliability and scalability – if configured appropriately, the entire system reacts more quickly and copes with a greater number of requests, because the load factor of servers can be balanced by redirecting specific requests to IIS (for static HTML, ASP and so on) and to SAP J2EE Engine 6.20 (all J2EE applications, JSP and so on).

Redirecting Requests by Filename Extension

IIS enables you to add external modules using either Internet Server Application Procedural Interface (ISAPI) Extensions or Filters. One of the ISAPI Extensions is InQMyForwardByFileTypeExt module – a lightweight version of connector between IIS and SAP J2EE Engine 6.20. ISAPI extensions are built as DLLs (Dynamic Link Libraries) and by default they are located in the <IIS_install_drive>/Inetpub/Scripts directory.

Installing the InQMyForwardByFileTypeExt Module

DLL files needed to perform the following installation process are located in <SAPj2eeEngine_install_dir>/tools/lib/IIS _ext and <SAPj2eeEngine _install_dir> /tools/lib/IIS_pref directories.

Install InQMyForwardByFileTypeExt module by completing the following steps:

Copy InQMyForwardByFileTypeExt.dll and InQMyForwardByFileTypeExt.ini files to your <IIS_install_drive>/Inetpub/Scripts directory.
Edit InQMyForwardByFileTypeExt.ini file using the appropriate settings for both variables.
Set InQMyServerHOST to an appropriate host (for example, localhost ).
Set InQMyServerPORT to an appropriate value (for example, 1080 ).
InQMyForwardByFileTypeExt.ini file must be copied to the same directory as InQMyForwardByFileTypeExt.dll , or the dll cannot run.
Configure IIS using

Microsoft Management Console ®Default Web Site ®Properties

Microsoft Management Console

Properties ®Home Directory – to define that the home directory must be located on the same computer

Home Directory

Configuring application configuration using Home Directory ®Configuration…

Application Configuration

Mapping InQMyForwardByFileTypeExt.dll to files with jsp extension. Every accepted request is directed to this dll .

Mapping to Files

You must restart IIS for the modifications to take effect; for version 6.20, the START and STOP commands are enough.

InQMyForwardByFileTypeExt.dll acts as a proxy and redirects all requests with jsp extension to SAP J2EE Engine 6.20. It supports “GET” and “POST” HTTP methods.

Redirecting Requests by Prefix

By using InQMyProxyFlt.dll and InQMyProxyExt.dll , the administrator can specify the requests to be forwarded to SAP J2EE Engine 6.20 in a separate configuration file ( InQMyProxyFlt.ini ), which contains the custom request forwarding rules.

For reliability, install ISAPI filter ( InQMyProxyFlt.dll ), ISAPI extension ( InQMyProxyExt.dll ) and a configuration file ( InQMyProxyFlt.ini ).

Note : The ISAPI filter ( InQMyProxyFlt.dll ) must be installed as a GLOBAL Filter, which accepts all requests on the server.

Installation Process

The dll files needed to perform the following installation process are located in <SAPj2eeEngine_install_dir>/tools/lib/IIS _ext and <SAPj2eeEngine
_install_dir>/tools/lib/IIS_pref directories.

To perform the installation process, complete the following steps:

Copy InQMyProxyExt.dll , InQMyProxyFlt.dll and InQMyProxyFlt.ini in the /Inetpub/Scripts directory of MS IIS. The filter cannot run if this directory is missing. For other releases, any directory with executing permissions can be set.
Edit the InQMyProxyFlt.ini file and set custom forward rules. The configuration file is a plain text file with the following format

If “#” is at the first token of a line, the whole line is a comment and is not processed.
Each line can contain a single entry – specifying rule of type – prefix ® host: port . This rule specifies that requests that begin with this prefix (that is, requests such as prefix/*) are forwarded to SAP J2EE Engine 6.20 running on the specified host and port. The port is optional and may be skipped (by default, it is port 80 ).
For example,
petstore® www.acme.com:8888 redirects requests that have prefix “/petstore/” (such as http://host_with_ms_iis/petstore/* ) to http://www.acme.com:8888/petstore/* . For more information, read the directions specified in the sample configuration file.

Note: InQMyProxyFlt.ini must be located in the same directory as InQMyProxyFlt.dll , or the dll cannot run.

If any additional changes to this file are made after the ISAPI filter has been installed and loaded by MS IIS, you must restart MS IIS for the changes in InQMyProxyFlt.ini to take effect.

Configure MS IIS to load the ISAPI filter ( InQMyProxyFlt.dll ). For the ISAPI extension ( InQMyProxyExt.dll ), no additional steps should be performed, other than copying it to the /Inetpub/Scripts directory of MS IIS.

Configuring MS Internet Information Server

To configure MS IIS to load the ISAPI filter ( InQMyProxyFlt.dll ), perform the following steps:

In the Microsoft Management Console right-click the server (machine) and choose “Properties.” Make sure you right-click the server, and not a single Web site on this server, because the filter has to be loaded as a global filter – that is, the filter takes effect on the whole server.

Internet Information Services

From the Properties option, the following dialog box appears for the server selected previously:

Properties Window

Choose “Edit” for the WWW Service. A second dialog box appears, with global settings for the WWW service (concerning the whole server):

WWW Services Master Properties

Select the “ISAPI Filters” tab. Choose “Add” to select the ISAPI filter to be added.

Filter Properties

In the dialog box that appears, type InQMyProxyFlt.dll in the “Filter Name” field, then choose “Browse” and select the InQMyProxyFlt.dll file that has already been copied in the /Inetpub/Scripts directory of MS IIS. Choose “OK” on all open dialog boxes.

Note: For every Virtual Site, a directory with Execute Permissions must be created and InQMyProxyExt.dll file must be copied for the filter to function properly. This scenario is shown below.

Different permissions for Scripts directory can be set.

Web Site Creation Wizard

Restarting IIS

After setting permissions for the Scripts directory, you must restart MS IIS for the changes to take effect. Right-click the server and choose “Restart IIS.” To verify that MS IIS has succeeded in loading the filter, choose “Properties” for the server and check the WWW Service settings. The loaded DLLs are displayed with a green arrow.

Note: If any changes are made to the configuration file with forward rules ( InQMyProxyFlt.ini ) after the ISAPI filter has been installed and loaded by MS IIS, you must restart MS IIS for the changes in InQMyProxyFlt.ini to take effect.