Migrating, coexisting, and interoperating
Learn the concepts and processes behind migrating various aspects of your existing product configuration to WebSphere® Application Server V9.0. These aspects include migrating servers and applications to use the new features and technologies provided by this version of WebSphere Application Server, such as Java™ EE 7.
Migrating your application servers
The goal of migrating your application servers to WebSphere Application Server V9.0 is for the migrated servers to behave as closely as possible to how they behaved in the previous release. After you migrate the servers, you can further configure them to use new features provided in V9.0.
Applications that are installed in the old environment are redeployed to the new application server without any changes. To use new technologies that are available in V9.0, you must update your applications. For information about migration toolkits that can help you migrate your applications, see the Migrating your applications section.
Regardless of the type of migration, you can use the command-line or GUI tools to migrate your product configuration as dependent on your operating system.
Migrating your applications

For more information and to download the toolkit, see the Migration Toolkit on WASdev.
Coexisting product installations
Coexisting is running multiple installations of WebSphere Application Server on the same machine at the same time. The installations can be the same version or different versions.
Interoperating product installations
Interoperating is exchanging data between two different product installations on the same machine or different machines that are at the same or different version. For example, an application can invoke a process that is supported by another application on a different machine. Another example is a V9.0 deployment manager managing a Version 8.5 federated node.