High Availability Java Enterprise Operations

High Availability Java Enterprise Operations

Java is still one of the most widely used programming languages. Especially in the enterprise environment, the use of Java for the development of web applications is often without alternatives. Accordingly, we had to set up an infrastructure for JavaEE operations for one of our customers in which a Java application can run fail-safe. The application uses a MySQL database as data storage.

The functionality of the application depends on the availability of the database, so it was necessary to run the database with appropriate replication and redundancy. For this purpose we use MariaDB with the replication layer Galera with a multi-master replication.

The application servers use a current Tomcat version with the corresponding application and an upstream HTTP load balancer (from Amazon AWS). However, the database access of the Java apps does not run directly to the DB servers, but via an intermediate instance of HAProxy. This makes it possible for us to detect database errors more quickly and to switch to intact nodes without the application itself having to know the status of the database.

Benchmarking Results

With this architecture, we achieve a performance of more than 1500 possible HTTP requests per second, with an average load of approx. 60 requests/s in normal operation.

Android App Minis@Rom

For a great service pilgrimage to Rome of the Catholic Church in Germany I was asked to develop the app Minis@Rom.

The special feature here was that the app could only use offline functionalities because of the very high roaming charges in Europe. The aim was to avoid high mobile phone charges for the mainly young pilgrimage participants.

Therefore, large parts of the app consisted of edited, static content such as the program, general information, various tourist information, a small dictionary and a great collection of sightseeing tours. There were also small games and an audio guide for selected routes.

The app was implemented with the framework of Apache Cordova. For the editors, a web-based possibility was created for the implementation phase to formulate parts of the content via Markdown, which was then automatically integrated into the app during the build process. For budget reasons, this app was released exclusively on the Google Play Store. As the app was developed exclusively for the duration of the pilgrimage, it was removed from the Play Store at the end of the event.