Run coexisting application servers

Create an environment that has coexisting product installations, which means we run multiple independent WebSphere Application Server installations and multiple nodes on the same system at the same time. The installations can be the same version or different versions, and we can choose whether they share a single web server installation. A major consideration in coexistence is the avoidance of port conflicts.

All combinations of WAS versions and editions can coexist so long as there are no port conflicts. For example, we can run a WAS (base) v8.5 installation and a WAS ND v9.0 installation on the same system if all of the ports are unique.

Clone migration will address many of the naming issues to ensure that the old and new cells can coexist. Ports, cell, node, server, and cluster short names, and procedure names will be different between the old and new cells so that both may run independently.

Reasons to set up coexistence

Reasons to not set up coexistence

We can achieve complete isolation between each WAS instance. We can uninstall one instance independently of the others. We can install the WAS (base) more than once on the same machine. We can install the WAS ND v7.0 or later product and the v9.0 product on the same machine.

The machine might have a hard disk space constraint. Use the operating system registry to locate the last installed instance of a WAS only. When we install any product a second time, the last installation is the one displayed in the registry. Uninstall the last instance removes any record of the product in the registry. Suppose that we installed three instances of WAS (base). We use the remove program function of the operating system to uninstall the registered third copy of the base product. A registry record no longer exists that indicates the existence of the other two installation instances. Other applications cannot use a query of the operating system registry to detect the presence of either WAS (base) product instance.

To install multiple instances of the same product version on a system, consider creating multiple profiles instead. One of the main goals of multiple-profile support is to minimize the need for having coexisting installations of the same product version. One reason that we might want to install coexisting instances of WAS v9.0 is a need to have different fix levels of the product on a single machine.

The system where we install multiple product versions or editions must meet all of the installation prerequisites for all of the products, such as the minimum Java and operating system requirements. For information about these requirements, see WAS detailed system requirements.

We can resolve conflicting port assignments by specifying port assignments for coexistence during profile creation, by wsadmin scripting, or using the Servers > Application Servers > server1 > Ports administrative console page to ensure that WAS v9.0 can run with an earlier version. For more information about wsadmin scripting, see wsadmin scripting tool.

Coexistence processing changes the following configuration files:

• virtualhosts.xml
  • HTTP transport port
  • IBM HTTP server port
  • HTTPS transport port
  • HTTP administrative console port
  • HTTPS administrative console secure port

• serverindex.xml
  • Bootstrap address
  • SOAP connector address
  • Data Replication Service (DRS) client address

    Deprecated feature: This port is deprecated and is no longer used in the current version of WAS.depfeat

  • Secure Authentication Service (SAS) SSL ServerAuth listener address
  • Common Secure Interoperability Protocol v2 (CSIV2) SSL ServerAuth listener address
  • CSIV2 SSL MutualAuth listener address
  • Administrative console port
  • HTTP transport port
  • Distribution and Consistency Services (DCS) unicast address
  • Administrative console secure port
  • HTTP transport secure port
  • Service Integration Bus (SIB) endpoint address
  • SIB endpoint secure address
  • SIB MQ endpoint address
  • SIB MQ endpoint secure address

See Port number settings.

Tasks

Install multiple instances of the product on a system. Be careful to avoid port conflicts, and optionally set up a shared web server. See Set up coexisting product installations.

Subtopics

• Set up coexisting product installations
  We can install WAS to coexist with another product installation instance as long as no ports conflict. When we install coexisting installations, we can share a single web server.