Running

Kapua can be run in a few different ways. See the following chapters for more information about how to start and run Kapua.

Docker containers

Before running Kapua on Docker, you need to

1. Install docker and docker-compose
2. Make sure that you have built Kapua docker images locally, following the provided building section of this documentation. Alternatively, you can utilize images hosted under the Kapua DockerHub account, for this case we recommend you to follow the "Quick Start Guide" section that can be found in the readme.md file under the root folder.

Now, you can start Kapua by using Docker Compose. To do so, run

kapua/deployment/docker/docker-deploy.sh

Note: in case of a deployment of and old version, assuming that you have built images for a release previous to 1.7.0, and consequently you have done a checkout to the proper tagged commit, keep in mind that the building procedure created a set of docker images tagged as "latest". The "docker-deploy" script pulls images tagged in this way. This implies that the newly built images will be launched.

After Kapua has been started, you can navigate your browser to http://localhost:8080 and log in using the following credentials: kapua-sys : kapua-password

You can access the API using: http://localhost:8081

Note: If you are using Docker on Windows the hostname will most likely not be localhost but the IP address of your docker instance.

To stop Kapua, run

kapua/deployment/docker/docker-undeploy.sh

OpenShift

OpenShift is a PaaS (Platform As A Service) platform based on Kubernetes. Kapua supports deployments into OpenShift Origin, which is an open source community project. Origin sources, can be found here. We support Kapua on OpenShift Origin 1.4.1.

Currently we support running OpenShift only on Linux OS. If you would like to run Kapua on Mac OS or on Windows for development purposes, please install Linux (for example Fedora 25) into a virtual machine (for example VirtualBox) and install OpenShift there.

Starting OpenShift cluster

For running Kapua on an OpenShift you need to have OpenShift cluster installed and started in the first place. You can install it by yourself or rely on the script we provides:

sudo kapua/deployment/openshift/openshift-start.sh

If you are running your OpenShift cluster for the first time, execute the following initialized script as well:

kapua/deployment/openshift/openshift-initialize.sh

Initialization script is responsible for logging you into a cluster and creating new OpenShift project for Kapua.

If your Openshift cluster is not on the localhost, set the OPENSHIFT_HOST environment variable. For example, something like

export OPENSHIFT_HOST=192.168.64.2:8443

If for some reasons, you cannot start your cluster, try to execute the startup script with option DOCKERIZED=FALSE:

sudo DOCKERIZED=FALSE kapua/deployment/openshift/openshift-start.sh

Option DOCKERIZED=FALSE tells startup script to use standard binary installation of OpenShift Origin instead of Docker-based oc cluster up command.

Deploying Kapua into OpenShift cluster

Now when you have OpenShift cluster up, running and initialized, execute the following script:

cd kapua/deployment/openshift
./openshift-deploy.sh

Now open the following URL in your web browser - http://localhost:8080. And log-in into Kapua UI using default credentials:

username

kapua-sys

password

kapua-password

Using Minishift

Minishift is a tool that helps you run OpenShift locally by running a single-node OpenShift cluster inside a VM. Follow this guide for installing and having Minishift up and running.

Steps to run Kapua on Minishift are the following

1. Start Minishift (make sure you have enough memory and cpu resources for your cluster)

    minishift start --memory 8GB --cpus 4
   

2. Export Minishift docker and oc tools

    eval $(minishift docker-env)
    eval $(minishift oc-env)
   

3. Export address of the cluster

    export OPENSHIFT_HOST=$(minishift ip):8443
   

4. Initialize Kapua project

    kapua/deployment/openshift/openshift-initialize.sh
   

5. Deploy Kapua components

    cd kapua/deployment/openshift
    ./openshift-deploy.sh
   

6. Visit Minishift console

    minishift dashboard
   

Advanced OpenShift configuration

External Node port for MQTT

The default setup uses port 31883 to export the MQTT over TCP port of the broker. This means that you can connect from outside of the OpenShift cluster to Kapua over port 31883 (instead of port 1883) to Kapua.

However it is only possible for one service to make use of this port. If you are planning to add a second Kapua installation and still want to use the external node port, then you will need to choose a different, yet unsed, port.

Also see: https://docs.openshift.com/container-platform/latest/dev_guide/getting_traffic_into_cluster.html

Adding metrics

If you have enabled metrics support in OpenShift (e.g. with oc cluster up --metrics) then you can also install Grafana for Hawkular to visualize your data:

oc new-app -f https://raw.githubusercontent.com/hawkular/hawkular-grafana-datasource/master/docker/openshift/openshift-template-ephemeral.yaml

External access

In order to enable devices to access Kapua we need to allow external access to the broker's MQTT connector. In the default deployment there are two ways to achieve this.

First, the broker exposes MQTT over WebSocket transport. As WebSocket is based on HTTP we can define a router inside the Openshift to get those device connections to the broker. For example, if your Openshift deployment is running at the address 192.168.64.2, you can connect the Kura Simulator like this

java -jar target/kapua-simulator-kura-*-SNAPSHOT-app.jar --broker ws://kapua-broker:[email protected]:80

Not all MQTT clients have WebSocket support, so we need to enable direct MQTT over TCP access to the broker as well. By default, Kapua comes with the NodePort service that routes all traffic from port 31883 to the broker. So you can connect your MQTT clients directly to this service. For the simulator example similar to the above, that would look something like

java -jar target/kapua-simulator-kura-1.7.0-SNAPSHOT-app.jar --broker tcp://kapua-broker:[email protected]:31883

This is suitable only for the local deployments. In the cloud or production environments, you should deploy a proper LoadBalancer Openshift service to enable external traffic flow to the broker.

Ensuring enough entropy

It may happen that firing up docker containers and starting up application which use Java's SecureRandom (which happens in the next step a few times) run dry the Linux Kernel's entropy pool. The result is that some application will block during startup (even longer than 30 seconds) which will trigger OpenShift to kill the pods since they are considered unresponsive (which they actually are).

You can check the amount of entropy the kernel has available with the following command:

 cat /proc/sys/kernel/random/entropy_avail

If this number drops to zero, then the kernel has run out of entropy and application will block.

One solution (there are a few others) is to install haveged a user-space daemon which provides entropy to the kernel.

On CentOS 7 it can be installed with the following commands (all as root):

 yum install epel-release # only if you
 yum install haveged
 systemctl enable --now haveged

As the package comes from the EPEL repositories. If you haven't yet enabled those repositories, then you need to do this before trying to install haveged:

 yum install epel-release

For more information about haveged see http://www.issihosts.com/haveged/

For more information about the "EPEL repositories" see https://fedoraproject.org/wiki/EPEL

Vagrant

Kapua can also be run with Vagrant.

Installing Vagrant

Before Vargant can be used to run Kapua it needs to be installed. This is different in each distribution.

Installing Vagrant on Fedora 25

Run the following commands in order to install Vagrant (all as root):

dnf install kernel-devel

wget https://www.virtualbox.org/download/oracle_vbox.asc
rpm --import oracle_vbox.asc

dnf install http://download.virtualbox.org/virtualbox/5.1.14/VirtualBox-5.1-5.1.14_112924_fedora25-1.x86_64.rpm
dnf install https://releases.hashicorp.com/vagrant/1.9.2/vagrant_1.9.2_x86_64.rpm

Running Kapua

After Vagrant is installed you can run Kapua by running:

cd dev-tools/vagrant
sudo ./start.sh base-box