The docker-stack.yml in the current folder will be used to deploy the voting app as a stack.Ensure you are in the first terminal and do the below:Note: being able to create a stack from a docker compose file is a great feature added in Docker 1.13.The output should be the following one. The benefit of multiple replicas is, that there are always more container running to takeover a service. I'm trying to set up a swarm using multiple physical hosts running docker Linux containers on windows host. Copy the below command into the first terminal.From the first terminal, check the number of nodes in the swarm (running this command from the second terminal The above command should output 2 nodes, the first one being the Let’s retrieve the voting app code from Github and go into the application folder.Ensure you are in the first terminal and do the below:A stack is a group of services that are deployed together.

Show members of swarm. Introduction. Please make sure to adjust your environment to fit your needs.After the common sudo apt update & sudo apt upgrade, we install Docker CE.Swarm is automatically part of the Docker CE installation, but we need to make some preparations.1 Node should be the manager, while the other nodes become worker nodes. E.g.

The purpose of this lab is to illustrate how to deploy a stack (multi services application) against a Swarm using a docker compose file.The voting app is a very handy multi containers application often used for demo purposes during meetup and conferences.It basically allow users to vote between cat and dog (but could be “space” or “tab” too if you feel like it).This application is available on Github and updated very frequently when new features are developed.There should be two terminals displayed. Use "docker swarm init" or "docker swarm join" to connect this node to swarm and try again. This post describes the installation of Docker swarm using Ubuntu 18.04 server virtual machines running on top of VMware vSphere.. After the installation and spinning up some container for ESXi, Ubuntu Linux and Docker Swarm. Creating a new swarm is a simple operation. EDIT 2017-10-06: Nowadays you can create the overlay network with --attachable flag to enable any container to join the network. Having multiple replicas means an instant takeover to the remaining replicas without any restart.When Docker publishes a port for a service, it does so by You can also create a service first and scale up later — lets deploy nginxYou can now simply check if Redis is responding on all nodes, despite the fact its only running on swarm1 and swarm2.This setup consists of multiple components: secrets, network, MariaDB Database service and WordPress service.Lets create the passwords for the root database and the wordpress database first and store them as a secret available on every Swarm node.Now we need a network connectivity across the cluster.If you visit any Docker Swarm node on Port 80 you should see the WordPress installer.sudo apt install apt-transport-https ca-certificates curl software-properties-commoncurl -fsSL # sudo vi /etc/hosts 192.168.0.12 swarm1 manager1 192.168.0.14 swarm2 worker1 192.168.0.15 swarm3 worker2docker swarm join --token SWMTKN-1-54hsijoskp3urbgeni9fqzz35yjzg527lvxxkg5qdg4ce7dqyz-bf1sladxf3t5v5wtl9droybdc 192.168.0.12:2377docker service create --name redis --replicas 2 --publish 6379:6379 redis# start with one service docker service create --name nginx-web --publish 8080:80 nginx# scale out to 3 replicas docker service scale nginx-web=3docker service ls ID NAME MODE REPLICAS IMAGE PORTS 8a0wumpvlm7u nginx-web replicated 3/3 nginx:latest *:8080->80/tcp hya01a0hl6k0 redis replicated 2/2 redis:latest *:6379->6379/tcpredis-cli -h 192.168.0.12 -p 6379 redis-cli -h 192.168.0.14 -p 6379 redis-cli -h 192.168.0.15 -p 6379openssl rand -base64 20 | docker secret create root_db_password - openssl rand -base64 20 | docker secret create wp_db_password -docker service create --name mariadb --replicas 1 --constraint=node.role==manager --network wordpress-net --secret source=root_db_password,target=root_db_password --secret source=wp_db_password,target=wp_db_password -e MYSQL_ROOT_PASSWORD_FILE=/run/secrets/root_db_password -e MYSQL_PASSWORD_FILE=/run/secrets/wp_db_password -e MYSQL_USER=wp -e MYSQL_DATABASE=wp mariadb:10.1docker service create --name wp --constraint=node.role==worker --replicas 1 --network wordpress-net --publish 80:80 --secret source=wp_db_password,target=wp_db_password,mode=0400 -e WORDPRESS_DB_USER=wp -e WORDPRESS_DB_PASSWORD_FILE=/run/secrets/wp_db_password -e WORDPRESS_DB_HOST=mariadb -e WORDPRESS_DB_NAME=wp wordpress:4.7 After the installation and spinning up some container for ESXi, Ubuntu Linux and Docker Swarm.This step is the preparation for a future post that covers monitoring of Docker Swarm and all components.The setup consists of 3 virtual machines running Ubuntu 18.04 LTS on vSphere 6.7.As its a test environment the VMs have been configured with 4 vCPUs, 8 GB RAM and 32 GB disk. Adding workers to a swarm.

This step is the preparation for a future post that covers monitoring of Docker Swarm and all components.

With a single host with a swarm that has been created with init, the host gets networks created etc. The first accesses the swarm Let’s create a Docker Swarm first. I'm running Windows 10 with the latest updates installed. If a container or container host would go down, Docker Swarm would restart the container of that service, but its not instant (can take some seconds). And it returns a nonzero exit code $ echo $? By default, the manager node generates a new root Certificate Authority (CA) along with a key pair, which are used to secure communications with other nodes that join the swarm.