Before you begin
Determine whether you have WebSphere Application Server for OS/390 V3.5 Standard Edition installed on the system where you plan to install your Version 5 product. If you are interested in utilizing the Simple Configuration Option for V4.0.1, then the content in this article will apply to you.Why and when to perform this task
To migrate V3.5 Standard Edition (hereafter referred to as V3.5SE) applications and configurations to Version 5, follow this procedure:
Steps for this task
Unlike V3.5SE, V5 and higher for the z/OS platform allows distributed platform Web servers for distributed platforms to communicate with the WebSphere Application Server for z/OS product. Refer to IBM WebSphere Application Server supported hardware, software, and APIs for supported distributed platform Web servers.
Note: V5, and higher, requires the use of SMP/E 3.1. Installation instructions have been provided with your ServerPac or PDO order.
Note: V5, and higher, does not conflict with the mount points or directory structure of the existing V3.5SE release.
There is no tooling support for migrating Server configurations because of the massive differences in application packaging/deployment, server structure/architecture, application administration compared to V3.5SE. This process will need to be done manually. Some key differences that should be noted:
Note: HTTP Transport is not a complete replacement for the IBM HTTP Server for z/OS. HTTP Transport has limited function when compared to IBM HTTP Server for z/OS.
Note: Prerequisites levels needed for WebSphere Application Server for z/OS may have changed from V3.5SE. Review these prerequisites at Prerequisites needed for WebSphere Application Server for z/OS.
The V3.5SE server executes as a GWAPI plug-in within the address space of an IBM HTTP Server for z/OS. Security policy for URLs (including those that get serviced by the WASv3.5SE plugin) that are served from the Web server are configured using the security directives in the httpd.conf file of that Web server. At runtime, the Web server is able to authenticate the user to the configured security server such as RACF or LDAP and determine if the user or a group that the user is a member of has been granted access to the specified URL before allowing access.
In order to migrate Web applications and their security policy from V3.5SE, as well as execute the server independent of the existing Web server, you need to insure that the deployment descriptor for the Web applications being migrated contains security constraints that match what currently exists within the httpd.conf. It is recommended to make use of the deployment descriptors within the Web application as a means for describing the security policy of the application.
V3.5SE does provide extended capability to supplement the Web server authorization processing by performing SAF checks against resources profiles that are defined in the SOMDOBJS facility class. If your existing V3.5SE servers use this capability, you will need to insure that you understand the policy and configure the equivalent within the deployment descriptor.
Either of these alternatives can coexist with the existing V3.5SE configuration. Alternatively, you may choose to continue to use an IBM HTTP Server for z/OS and OS/390, in which the V5 WebSphere HTTP Plug-in for z/OS has been installed. In this case, the IBM HTTP Server for z/OS and OS/390 you are using must be at a V5.3 level.
With this in mind, several migration configurations are possible:
What to do next
Migration from Version 4.x to Version 5, or higher, does not require extensive tuning.
Migration from Version 3.5.x to Version 5, or higher does require you to examine the migrating applications.
After planning for migration and coexistence, you are ready to continue the installation.