Vagrant Docker Swarm cluster setup

Automatic Docker Swarm cluster setup with Vagrant and Ansible

Prerequirements

The following software should be installed:

• Vagrant
• Vagrant Virtualbox plugin:

vagrant plugin install virtualbox

• Ansible
• Python cryptography library

Running

Just run:

$ vagrant up

and wait for setup to complete

Hosts

• apt-proxy - utility host with apt-cacher-ng to reduce network traffic
• manager-1 - first Docker Swarm manager
• manager-2, etc... - additional Docker Swarm managers
• worker-, etc... - Docker Swarm workers

Configuration

Vagrant file contains following constants:

• IMAGE_NAME = "ubuntu/focal64" - Vagrant box image. "ubuntu/focal64" - the only one is supported
• WORKERS_COUNT = 2 - Workers count
• ADDITIONAL_MANAGERS_COUNT = 2 - Additional Docker Swarm managers count
• SUBNET_BASE = "192.168.200." - Private subnet address
• APT_PROXY_IP = SUBNET_BASE + "2" - apt-proxy ip address
• FIRST_MANAGER_IP = SUBNET_BASE + "3" - manager- ip address
• DOMAIN = 'local' - domain

Ansible roles

The following roles are used:

• apt-proxy - setup apt-cacher-ng with docker repo proxy
• apt-setup - Vagrant related. Disable unattended updates
• deploy-portainer - Deploy portainer stack on cluster
• deploy-traefik - Deploy traefik reverse-proxy stack
• docker-install - Install and configure Docker CE
• swarm-first-manager - Initialize Docker Swarm cluster and copy join tokens to ansible host
• swarm-join-node - join swarm node to previously configured cluster using join token

Ansible playbooks

• apt-proxy-playbook.yml - setup apt-proxy
• first-manager-playbook.yml - setup manager-1
• swarm-node-playbook.yml - setup swarm nodes

Aliases

Redirect ports to host:80 and host:443 Add the following lines to /etc/hosts

127.0.0.1      portainer.<DOMAIN_NAME>
127.0.0.1      traefik.<DOMAIN_NAME>

Port redirection

Add port redirection to services to be available on 80 and 443 ports:

sudo iptables -t nat -I OUTPUT -p tcp -d 127.0.0.1 --dport 80 -j REDIRECT --to-ports 8080
sudo iptables -t nat -I OUTPUT -p tcp -d 127.0.0.1 --dport 443 -j REDIRECT --to-ports 8443

Remove port redirection:

sudo iptables -t nat -D OUTPUT -p tcp -d 127.0.0.1 --dport 80 -j REDIRECT --to-ports 8080
sudo iptables -t nat -D OUTPUT -p tcp -d 127.0.0.1 --dport 443 -j REDIRECT --to-ports 8443

Work with remote docker

Create docker context:

$ docker context create vagrant --docker host=ssh://vagrant@localhost:2222

Add vagrant ssh key:

$ eval $(ssh-agent)
$ ssh-add ~/.vagrant.d/insecure_private_key

Invoke docker command on remove host

docker --context vagrant ps