How to move your applications

Moving applications from one server to another

The package command can be used to help move your applications. package produces a ZIP file of the application directory, which can then be transferred and unzipped onto another server.

1. Start by invoking zero package in the application's home directory. For example, to package application myapp located at C:\zeroapps\myapp, change directory to C:\zeroapps\myapp then invoke zero package.
2. Transfer the generated ZIP file to the other server. (Console output from zero package includes a pointer to the generated file, which will be located in the application's export directory.)
3. Extract the ZIP file on the other server. Note that the ZIP file includes the application directory. For example, extracting the ZIP file into D:\other\zeroapps yields the new application home directory at D:\other\zeroapps\myapp.
4. Resolve the application by invoking zero resolve from the application's home directory. Even if versions don't change, this step is required to fix the paths to modules in the local repository.

Migrating applications to another module group

1. Install the WebSphere sMash command-line interface (CLI) using the installer (available from IBM).
2. Migrate each application to the "stable" module group by invoking zero switch stable in the root directory of the application. For example, to switch application myapp located at C:\zeroapps\myapp, change directory to C:\zeroapps\myapp then invoke zero switch stable .

Evaluating the success/failure of the migration

Migration should be treated like any other change in software development.

Successful migration means that the application runs correctly with the new dependencies. Before you can claim success, you must complete the migration steps, then perform adequate testing within the new run-time environment.

The following pointers might help you along the way.

Interpreting console output from the switch command

The switch command performs the equivalent of an update command after changing the module group. This will succeed as long as the dependencies can be satisfied from the new module group. If those dependencies are already available in the local repository, then the console output will be simple, such as:

switch can also succeed by retrieving missing dependencies from the remote repository. The corresponding console output describes the operation, such as:

switch fails if it's unable to obtain the dependencies. One cause of failure would be if the application used a not-yet-released module from the experimental module group. The console output indicates the problem and cancels the switch operation, such as: