Creating Overlay Networks and Testing Container Connectivity

Docker Part 2 Assignment - 5

Tasks To Be Performed:

1. Use the previous assignment’s deployment
2. Deploy any 2 containers in a overlay network
3. Try pinging each of the containers from within the containers

Step 1: Previous Deployment §

Using previous Assignment 4 – Docker – II’s Deployment

Instances Private IPs

master 10.0.1.199 worker1 10.0.1.176 worker2 10.0.1.38

Step 2: Deploy Two Containers in an Overlay Network §

In this step, I will deploy two containers within an overlay network in the Docker Swarm cluster. An overlay network enables seamless communication between containers across different nodes in the Swarm. To achieve this, I will use the following commands:

# Create an overlay network (if not already created)
docker network create --driver overlay my-overlay-network
 
# Deploying two containers in the overlay network
docker service create --name container-1 --network my-overlay-network alpine ping 8.8.8.8
docker service create --name container-2 --network my-overlay-network alpine ping 8.8.8.8

Step 3: Ping Containers from Within Containers §

I find out which node I need to ssh into

docker service ps <container-1>

So the containers are in worker1 10.0.1.176 and worker2 10.0.1.38

I SSH into worker1 and subsequently log into ‘container-1,’ enabling me to ping ‘container-2’.

Success

This time, I SSH into worker2, which allows me to log into ‘container-2.’ From within ‘container-2,’ I execute a ping command to reach ‘container-1’.

Success