We are currently working in a project where we use Orion ContextBroker to store information from different sensors and Wirecloud to show them in a web page.
We want to store historical data from these sensors in order to show them in a graph. I have looked around the Fiware documentation and they recommend to store the data in a Cosmos instance of Fi-lab, through Cygnus.
The thing is that we would like to store that historical data in a local Hadoop based server we have in our company, not in Cosmos, because we are running this project in a local net where we don't have internet access, and also to have that information stored in our local server.
Is it possible to configure Cygnus to redirect the output data to my file system? If so, which files must be configured in order to achieve this?
The answer is yes. Cygnus is meant to persist context data in whatever HDFS-based filesystem (as the one used by Cosmos), thus nothing special has to be done when configuring Cygnus.
If you download the lastest version (0.7.0 at the moment of writting this), you will need to configure:
cygnus_instance.conf.template. This is the instance configuration. From 0.7.1 is possible to have multiple instance configurations that are run in a parallel way, and they all have to called
agent.conf.template. This is the Flume specific configuration that you will find in the README.md.