Launching Tasks

The following information describes how to launch Calico networked tasks in Mesos using sample Marathon application definitions.

Unified Containerizer

Launch a Unified Containerizer task onto a Calico network by setting networkName to the name of your Calico network. Its value should match the "name" field of the calico.conf you configured when Installing Calico for Mesos

{
  "id": "unified-task",
  "cmd": "/usr/sbin/ip addr show && sleep 1000",
  "ipAddress": {
      "networkName": "calico"
  }
}

Note: Replace /usr/sbin/ip with the correct path to your IP binary.

The task’s stdout output should show a Calico IP from the default Calico pool of 192.168.0.0/16.

Docker Containerizer

To launch a Docker Containerizer task, first create a Docker Network to launch it on:

docker network create --driver=calico --ipam-driver=calico-ipam calico-nginx

Then in your marathon application definition, set network to USER, and set networkName to the name of your Calico network:

{
  "id": "docker-task",
  "container": {
    "type": "DOCKER",
    "docker": {
      "image": "nginx",
      "network": "USER"
    }
  },
  "ipAddress": {
      "networkName": "calico-nginx"
  }
}

Enabling Health Checks

Marathon supports Health Checks for IP per container applications. Health Checks should specify a port (instead of the portIndex field which is commonly used for port-mapped applications).

For the Health Check to succeed, the following conditions must be met:

1. The host running Marathon will need routes to Calico tasks. If you are running Marathon as a Mesos task, and have already installed Calico on each Agent, you have met this requirement.

2. Calico Networking Policy should permit the health check from Marathon to the target application.

The following sample application launches a nginx webserver with healtchecks:

{
  "id": "nginx",
  "container": {
    "type": "DOCKER",
    "docker": {
      "image": "nginx",
      "network": "USER"
    }
  },
  "ipAddress": {
      "networkName": "calico"
  },
  "healthChecks": [{
      "protocol": "HTTP",
      "path": "/",
      "port": 80
  }]
}

The following Calico Profile yaml will allow the health check from an instance of Marathon running at 172.24.197.101:

cat << EOF | calicoctl apply -f -
apiVersion: projectcalico.org/v3
kind: Profile
metadata:
  name: calico
spec:
  ingress:
  - action: allow
    protocol: tcp
    source:
      nets:
      - 172.24.197.101/32
    destination:
      ports: [80]
EOF

Next

Connecting to Tasks