High-Available Wordpress PoC on Docker Swarm 1.12.x with MariaDB Galera cluster.

ha-wordpress.service

#! /bin/bash

wordpressPath=/srv/wp01
wordpressName=wordpress01
wordpressPwd=pAssw0rd
wordpressUrl=wordpress01.example.com

##################################

mkdir -p "$wordpressPath"/db
mkdir -p "$wordpressPath"/www

docker network create --driver=overlay $wordpressName

docker service create --name "$wordpressName"-db-cluster \
	--network $wordpressName \
	--replicas=1 \
        --env MYSQL_ROOT_PASSWORD=$wordpressPwd \
        --env MYSQL_DATABASE=wordpress \
	--env DB_SERVICE_NAME="$wordpressName"-db-cluster \
        --mount type=bind,source="$wordpressPath"/db,target=/data \
	valentinnc/mariadb-galera:10.1

sleep 2

docker service create --name wordpress01 \
--replicas 1 \
--network $wordpressName \
--network traefik-net \
--label traefik.port=80 \
--label traefik.frontend.rule=Host:"$wordpressUrl" \
-e WORDPRESS_DB_HOST="$wordpressName"-db-cluster \
-e WORDPRESS_DB_PASSWORD=$wordpressPwd \
-e WORDPRESS_DB_USER=root \
--mount type=bind,source="$wordpressPath"/www,target=/var/www/html \
wordpress:latest

echo
echo "You can scall up services with theses commands :"
echo
echo "docker service scale "$wordpressName"-db-cluster=3"
echo "docker service scale "$wordpressName"=3"

traefik.service

docker network create --driver=overlay traefik-net

docker service create \
 --name traefik \
 --publish 80:80 --publish 443:443 --publish 8080:8080 \
 --mount type=bind,source=/var/run/docker.sock,target=/var/run/docker.sock \
 --mount type=bind,source=/srv/traefik/traefik.toml,target=/etc/traefik/traefik.toml \
 --network traefik-net \
 --mode global \
 traefik:v1.1.0-rc1 \
 --docker \
 --docker.swarmmode \
 --docker.domain=example.com \
 --docker.watch \
 --logLevel=DEBUG \
 --web

traefik.toml

################################################################
# Web configuration backend
################################################################
[web]
address = ":8080"
################################################################
# Docker configuration backend
################################################################
[docker]
endpoint = "unix:///var/run/docker.sock"
watch = true
swarmmode = true

This configuration provide a High-available Wordpress using MariaDB Galera Cluster.

• It work from scratch in a singleNode Swarm cluster.
• If you have multi-nodes, you need to sync the $wordpressPath folder between hosts using GlusterFS or Btsync for example.
• You can scale-up App and DB containers.