Appboard/2.4/admin/multiple instances

Multiple instances of AppBoard can be configured to run on the same system. This article details some of the considerations to have this work correctly.

Why Multiple Instances?

The following are some sample cases where you may want to install more than one instance of AppBoard on the same server:

• Testing - The test team needs to have multiple versions of the system available so they can validate the functionality and features against one another.
• Development - A developer is working on multiple AppBoard development projects at the same time.
• Staging - A production and dev system are both running on the production server. They can be swapped, for example, to make the dev system become the production system after validation is complete and certified.
• Demos - Multiple demo systems can be created and provided at the same time for review.
• Multi-homed server - have different copies of AppBoard running for different target networks.

Configuration

Refer to the Runtime Options page for a complete listing of options and how to configure, but for the purposes of running multiple copies of AppBoard on the same server the following are critical:

Option	Description
HTTP_PORT	Each instance will need to listen on a different port.
SHUTDOWN_PORT	Each instance will need it's own shutdown port.
HTTP_ADDRESS	(optional) for multi-homed systems, restrict AppBoard to listen only on a specific IP address.

When running multiple AppBoard instances the total memory usage of all AppBoard copies needs to be considered with respect to the total available memory on the server. Refer to the Memory Configuration page for more information

On Linux/UNIX systems it's possible to install multiple system services for multiple AppBoard instances on the same server, as long as each service is given it's own unique name.

Database Configuration

If you are using the default AppBoard database settings and the embedded local AppBoard H2 database, no special configuration is required to run multiple instances on the same server. Each instance ill use it's own database.

If your system is configured to access an external database, such as Oracle or MySQL, then care must be taken. If you have two systems running locally that are accessing the same database, unpredictable results may occur. For example, if you add a test User on the dev instance, and this is connected to the same database as the production instance, the test User will also appear in the production instance.