Marathon is the native container-orchestration and application platform for the Mesosphere Datacenter Operating System, and Marathon 0.14 includes many exciting improvements. These include simplified networking, improved network security and service discovery, as well as continued debugging and monitoring improvements in the web interface—including direct access to the full stderr and stdout logs.
Many of these features, which are explained in detail below, take advantage of updates in
Mesos 0.26. Therefore, we recommend using Marathon 0.14 with Mesos 0.26.
Experimental networking features
It's now possible to require an IP address for each task. This makes networking simpler because, with the appropriate configuration, each task is individually addressable, just as it would be in a traditional static cluster.
Even better, Marathon 0.14 provides enough information for mesos-dns to discover SRV records for simplified service discovery.
Finally, new network security groups and labels make it possible to restrict network traffic between tasks.
Resource awareness
In Marathon 0.14, applications have access to their allocated resources via environment variables. This means that an application can rotate its logs based on its disk resource quota, for example. Applications can also access their definition name and labels by the same mechanism. Environment variables also provide access to the definition name and labels of each application.
Debugging
The latest Marathon web interface shows the Mesos sandbox in each task, and you can now download the full stderr and stdout logs directly. This makes access to logs much simpler than previous versions, where they were only accessible through the Mesos web interface.
[caption id="attachment_4081" align="alignnone" width="800"]
Image 1. Access to logs from the Marathon web interface.[/caption]
We've also simplified health checks. Now you can sort applications by health status, and the health bars themselves have been consolidated to make them easier to read.
Full search
We've replaced a simple filter mechanism with more powerful search capabilities and a detailed results page that preserves context and reflects application groups.
[caption id="attachment_4082" align="alignnone" width="800"]
Image 2. More powerful search functionality in Marathon 0.14.[/caption]
Mesos users can upgrade to Marathon 0.14 now to take advantage of these new features. It will also be included as part of the next Mesosphere DCOS release, which should be available soon.