1 Introduction

This document describes the process of moving an existing application, unchanged, to WebLogic Server 12c Release 1 (12.1.1). Although you may decide to change your application when upgrading to WebLogic Server 12.1.1, and although in some cases, you must change your application, this document focuses on issues that you should consider when moving an application to WebLogic Server 12.1.1 without making application changes.

WebLogic Server generally supports very high levels of upgrade capability across WebLogic Server versions. This document is intended to provide WebLogic Server upgrade support and identify issues that may surface during an upgrade so that they can be easily resolved.


For information about upgrading your Java EE environment and your deployed applications from Oracle Application Server 10g and Oracle Containers for Java EE (OC4J) to WebLogic Server 12c Release 1 (12.1.1), see Oracle Fusion Middleware Upgrade Guide for Java EE.

Oracle does not require WebLogic domains to be upgraded from WebLogic Server 10.3 to 12.1.1. WebLogic domains based upon WebLogic Server 10.3 run on WebLogic Server 12.1.1 without modification.

WebLogic Server 12.1.1 includes powerful tools to assist you with upgrading your application environments, including the WebLogic Upgrade Wizard for upgrading domains, custom security providers, and custom node managers.

Most WebLogic Server applications can be run without modifications in the new WebLogic Server 12.1.1 application environment.

The following topics are discussed in this chapter:

Important Terminology

We recommend that, before proceeding, you familiarize yourself with the following terminology:

  • Upgrade—In this document, the term upgrade refers to the process of moving an existing application, unchanged, to a new (upgraded) WebLogic Server version.

  • Application Environment—An application environment includes applications and the WebLogic domains in which they are deployed. It also includes any application data associated with the domain, and may include resources such as database servers, firewalls, load balancers, and LDAP servers.

  • Migrate—To move an application or domain configuration from a third-party product to an Oracle product.

  • Interoperability—(1) The ability of an application deployed in one WebLogic Server version to communicate with another application that is deployed in a different WebLogic Server version. (2) The ability of Oracle product components to communicate with third-party software using standard protocols.

  • Compatibility—The capability of an application built using one WebLogic Server release to run in another another WebLogic Server release, regardless of whether the application was rebuilt.

Overview of the Upgrade Process

The process required to upgrade an application environment depends on the scope of the application. An application environment includes a WebLogic domain and any applications and application data associated with the domain. It may also include external resources, such as firewalls, load balancers, and LDAP servers. Figure 1-1 shows an example of a WebLogic application environment.

Figure 1-1 Example WebLogic Application Environment

Description of Figure 1-1 follows
Description of "Figure 1-1 Example WebLogic Application Environment"

Table 1-1 lists the components of the WebLogic application environment shown in Figure 1-1 and the upgrade requirements for each.

Table 1-1 Upgrade Requirements for Components in Example WebLogic Application Environment

Component Description Upgrade Requirements

WebLogic domain

Includes the Administration Server (AS) and optionally one or more Managed Servers (for example, MS1, MS2, MS3, and MS4). The servers in a domain may span multiple machines. Furthermore, you can group Managed Servers into clusters to support load balancing and failover protection for critical applications. For more information about WebLogic domains, see "Understanding Oracle WebLogic domains" in Understanding Domain Configuration for Oracle WebLogic Server.

Upgrade the domain directory on each computer in the domain.

Custom security provider

Supports custom security requirements. For information about developing custom security providers, see Developing Security Providers for Oracle WebLogic Server.

Upgrade the custom security providers on each computer in the domain.

Node Manager

Provides high availability to Managed Servers. For more information about Node Manager, see "Node Manager Overview" in Node Manager Administrator's Guide for Oracle WebLogic Server.

Upgrade custom Node Manager on each computer in the domain.


Any Java EE applications, including Web applications, EJBs, and so on. Typically, applications are deployed to one or more Managed Servers in a domain. Depending on the deployment strategy, applications may reside locally on a computer or be accessible using a shared directory. In addition, external client applications may access the application environment from outside a firewall.

Most WebLogic Server applications can be run without modifications in the new WebLogic Server 12.1.1 application environment. For more information, see Interoperability and Compatibility with Previous Releases.

External resources

Software components, such as databases for storing domain and application data, load balancers, and firewalls.

Verify that all external resources are compatible with WebLogic Server 12.1.1. For more information, see the Oracle Fusion Middleware Supported System Configurations page.

Upgrading business applications that are deployed to WebLogic Server may involve upgrading multiple WebLogic Server applications, and in some cases domains, in a coordinated fashion in order to:

  • maintain consistency in the WebLogic Server versions being used

  • use the same supported configurations environment across the entire installation

  • meet specific interoperability requirements.

For example, you may want to upgrade all applications and domains simultaneously, upgrade them in a well-defined sequence, or upgrade some applications and domains while leaving other applications and domains on older WebLogic Server versions.

Before You Begin

Before you begin the upgrade process, you should consider the scope of the environments that you are upgrading and which applications will be upgraded in which sequence. Covering all of the permutations of an upgrade is beyond the scope of this document. Therefore, you should consider the following items prior to planning your upgrade. These items focus on upgrades that involve a single application running in a single domain.

  • Oracle generally recommends that you upgrade an application in development environments and use a standard QA, testing, and staging process to move upgraded applications to a production environment.

  • You will typically upgrade an application either by upgrading an existing domain or by creating a new domain, from which you can run the application on the new WebLogic Server version. The Domain Upgrade Wizard supports upgrading of domains from older WebLogic Server versions to newer WebLogic Server versions.

    The Domain Upgrade Wizard upgrades domains from older WebLogic Server versions to newer WebLogic Server versions. If you upgrade a domain, you do not need to recreate domain configurations, and you can leverage existing domain configurations that are know to support your existing applications.

    There will, however, be cases where you may prefer to create new domains using the Fusion Middleware Configuration Wizard or other configuration tools (such as WLST) in order to test the applications that you are upgrading.

  • When planning a WebLogic Server version upgrade, you should review the Fusion Middleware Supported Systems Configurations page to ensure that your upgraded environment is supported by Oracle, in particular:

    • current and planned JVM and JDK versions

    • operating system versions

    • database versions

    • Web services versions

    • versions of other products that interoperate with or run on WebLogic Server, to ensure that the upgraded environment is supported by Oracle or other vendors' products that you are using with WebLogic Server.

  • On an ongoing basis, Oracle documents APIs and features that have been deprecated (that is, planned for removal in a future release). This is intended to inform you that you should avoid using these APIs and features to ensure upgradeability. Oracle also documents the APIs and features that have actually been removed in the current release so that if you are upgrading from prior versions, you can determine if your applications will be affected by an upgrade.

    APIs and feature removals are cumulative. For example, if you are upgrading from WebLogic Server 10.0 to WebLogic Server 12.1.1, your applications may be affected by APIs or features that were removed in WebLogic Server 10.3, as well as by APIs or features that were removed in WebLogic Server 12.1.1. When upgrading, you should review all documentation of deprecated and removed features for all applicable WebLogic Server versions.

  • You should consider the impact (if any) that the upgrade process may have on any automation (such as WLST scripts) that you are using to configure, deploy, start/stop, or monitor your WebLogic Server applications. You may need to upgrade such automation along with the applications and domains you are upgrading.

  • You should consider the potential impact that may result from the use of third-party libraries in your applications, as they may conflict with different versions of those same libraries that are embedded in WebLogic Server. In particular, new versions of WebLogic Server my change the version of open source libraries that are embedded in WebLogic Server. Applications that may run successfully on earlier WebLogic Server versions may encounter new class conflicts after upgrade.

    If you are upgrading an application that contains embedded third-party libraries, you should consider using the Classloader Analysis Tool, and filtering classloaders when upgrading WebLogic Server applications to WebLogic Server 12.1.1. This tool enables you to identify, diagnose and resolve such conficts, and may simplify the upgrade process.

  • If you are running applications on prior versions of WebLogic Server, and are using WebLogic Server patches or bug fixes, you should investigate whether or not those patches or bug fixes have been incorporated into the version of WebLogic Server to which you are upgrading.

How the Upgrade Wizard Simplifies the Upgrade Process

The WebLogic Upgrade Wizard guides you through the steps required to upgrade a WebLogic Server 8.1 domain such that it runs in a WebLogic Server 12.1.1 application environment. As part of the upgrade process, you must upgrade any custom security providers and Node Managers used in the domain.

You can also use the WebLogic Upgrade Wizard to upgrade to a WebLogic Server 12.1.1 domain that is compatible with WebLogic Server 9.x or 10.x, but this is optional. This type of domain runs under WebLogic Server 12.1.1 without modification.

You can step through the upgrade process interactively, using the graphical user interface (GUI), or "silently", by creating an upgrade script and running it. Silent Mode is supported for upgrading a WebLogic domain, security providers, and Node Manager.

Interoperability and Compatibility with Previous Releases

Application environments that run with WebLogic Server 12.1.1 can interact with application environments built on WebLogic Server 8.1, 9.x, 10.0, or 10.3.

Most existing WebLogic Server applications can be run without modification in the new WebLogic Server 12.1.1 application environment. You should review the compatibility information described in Appendix A, "WebLogic Server 12.1.1 Compatibility with Previous Releases," to determine whether any feature changes affect the applications in your environment. If your application uses APIs that have been deprecated or removed, then you may encounter warnings or exceptions at run time.