Technical FAQ

In which platforms has been Sentilo tested ?

The first deployment for the Barcelona City Council has the following infrastructure:

  • Four virtual machines, two for the front-ends and another two for the back-end
  • All of them use as operating system Ubuntu server LTS 18.04
  • The real time database server(Redis) works with 32 GB of memory and 36 GB of hard disk
  • The other three servers work with 4 GB of memory and 16 GB of hard disk

Another deployment configurations should work properly, always keeping in mind the expected load by the system.

All known Sentilo instances are deployed on Linux servers, mainly CentoOS 6+ and Ubuntu Server 14.04+.

I successfully published an observation, but I cannot see the data in catalog.

Check that the Catalog and Sentilo API Server are in the same timezone, for example in UTC. Make sure the sentilo-server is executed with the following VM option:


Also, make sure that the Tomcat that hosts the Catalog application has the same option, for example en $JAVA_OPTS variable.

Google Maps is not showing up in Catalog application

Recently Google changed it policy regarding Maps key. Please go to and create one.

You can define the API key inside the /etc/sentilo/sentilo-catalog.conf configuration file:

# Google API key to use Google Maps<your key>

Remember you’ll have to restart tomcat in order to let sentilo-catalog-web.war reload these changes.

I created a provider and immediately after that, an observation using the new provider’s token is rejected with 401 “Invalid credential”

The providers are activated in a background job that runs every 5 minutes. Please wait a moment :-)

Another possible reason is that the Sentilo API server started before the Catalog application (probably deployed on your Tomcat).

At startup, the API server performs a call to:


in order to mirror the permissions stored in MongoDB with Redis.

If this call fails because the sentilo-catalog-web is not deployed yet, the permissions are not correctly created. To resolve the issue, reboot your Sentilo and ensure that the API server starts always after the sentilo-catalog-web is fully deployed.

The command mvn package appassembler:assemble fails.

You have to execute the command in the directory of the component you want to install.

I think I installed Sentilo. How can I confirm all is up & running?.

You can use this script:


You also might want to check Platform Testing

If you installed everything on your local machine, you can access the catalog at http://localhost:8080/sentilo-catalog-web and the REST API at http://localhost:8081

How can I activate debug logs?

You can pass the property sentilo.log.level to the JVM. For example, you might add the following code to the script in the bin directory of the component you want to debug: