Jboss

Starting and stopping Docker containers is easy with the docker run and docker {stop|kill} commands. By default, when the Docker daemon is restarted, running containers are also restarted. This is a great feature but sometimes you need more control over the container’s lifecycle. Imagine having a container which is linked to another one. Docker does not provide any way of specifying which container should be started when or what to do if a container dies. ...

Default configuration is a great place to start with a project. We at JBoss try to make our projects (and products too!) usable out-of-box for as many use cases as we can, but there is no way that one configuration could satisfy everyone’s needs. For example, we ship 4 flavors of the standalone.xml configuration file with WildFly since there are so many different deployment scenarios. But this is still not enough. We need to be able to tweak it at any point. The jboss/wildfly image is not an exception here. ...

There are various ways to set up logging for Docker containers. Docker itself has a built-in logs command, you can mount a volume from the host and save the logs there, you can create a different container that would be only responsible for log handling, or set up a logging daemon. Every method has some pros and cons and it is up to you to choose the one that fits best. ...

I recently announced the availability of the official WildFly Docker image. Since then, our portfolio of images has grown a bit - as of today, we have 8 images. But this is not the end. We want to have a nice collection of JBoss projects shipped as Docker images. Automated builds All of our images are hooked up to automated builds. When we push an update to the repository, a new image will be created and pushed to the global registry. I also set up links between the images so if a base image is updated, our dependent images will be rebuilt. This is a fully automated process that ensures you get the latest available software. ...

The default way of creating an image with Docker is to extend an image by using the FROM call in the Dockerfile. But this is not the only way to do this. You can easily create a base image by using only the yum command. WildFly 8.0.0.Final was recently released and is now available in Fedora 20 updates-testing repository. Let’s create an image that could be used to test this release but make it as minimal as it could be. The application server does have a lot of dependencies, so do not expect a 100 MB image. It’ll be closer to 1 GB. ...

What and why I am always sad seeing all the potential damage done to your local system, just to set up your development environment. Every time you do almost the same thing, every time you mess your system up in almost the same way. It really doesn’t matter in which language you’re wrtiting and what frameworks you use but Java (and Maven) is a pretty good, uhm, example. A development environment is not only about IDE and JDK, in almost all cases we need to have an application server too. We set it up; our application works great on it, but when we deploy it to production we experience deployment issues. Some things changed: we have different JDK, different network interfaces and so on. Everything can affect your application. ...

In my previous blog post I introduced Docker and its Fedora integration. Now it’s time to do some serious (read: useful) stuff. A few years ago I started a project called CirrAS. It’s dead now, but the main idea behind it was to form a cluster of JBoss AS servers in the cloud, without any unnecessary steps. You just launched the instances, they found and connected to each other and the result was a working cluster. Additionally every cluster node registered itself in a front-end instance which worked as a load balancer and monitoring/management (we used RHQ) node. ...

I haven’t been giving talks lately. There were various reasons for it; but the most important is that I was busy with the Fedora/JBoss AS stuff for quite some time. The good (?) news is that I’m back to real programming. Since a couple of months I’m helping with TorqueBox, expecially in the messaging space. This is a great opportunity to share this cool stuff with people. I’ve decided to submit my first ever talk to GeeCON and it was accepted, yay! I know the conference pretty well and I enjoy it every time I’m attending. This is also true to the OpenSpaces co-event which is held the day after the main conference (this year it’s 18th May). For more information about the conference please reach out to the conference page. ...