Create a "simple" docker swarm cluster : 1 data node, 1 master node, 2 workers

docker-cluster-create.sh

#!/bin/bash

set -e
#
# Create a cluster of workers on exoscale, sharing a common data folder using a NFS exports. 
# (not battle tested)
#

# BASED ON THE ENTIRE WEB and those sources
# https://www.digitalocean.com/community/tutorials/how-to-set-up-an-nfs-mount-on-ubuntu-16-04
# http://www.blog.labouardy.com/docker-swarm-networking-and-dynamic-reverse-proxy/



NODE_PREFIX_="mx-node-"
NODE_DATA=$NODE_PREFIX_"data"
NODE_MASTER=$NODE_PREFIX_"1"
N_NODES_WORKERS=$(seq 2 3)
N_NODES_ALL="1 "$N_NODES_WORKERS 
DIR_HOST=/home
DIR_WORKER=/nfs/home
DIR_WORKER_SHARED=$DIR_WORKER/shared
DOCKER_MACHINES=$(docker-machine ls -q)
SYS_USER="ubuntu"
SYS_USER_CHOWN=$SYS_USER":"$SYS_USER

EXO_TOKEN=$EXOSCALE_API_KEY
EXO_SECRET=$EXOSCALE_SECRET_KEY
EXO_REGION=ch-dk-2

#
# Create data machine
#
if echo $DOCKER_MACHINES | grep $NODE_DATA ;
then echo $NODE_DATA "already exists";
else

  docker-machine create \
    --driver exoscale \
    --exoscale-api-key=$EXO_TOKEN \
    --exoscale-api-secret-key=$EXO_SECRET \
    --exoscale-availability-zone=$EXO_REGION \
    --exoscale-image=ubuntu-16.04 \
    --exoscale-disk-size=50 \
    --exoscale-instance-profile=Tiny \
    --exoscale-ssh-user=$SYS_USER \
    $NODE_DATA;
fi

if [ ! -e $DIR_HOST ]
then
  docker-machine ssh $NODE_DATA sudo mkdir -p $DIR_HOST
fi
docker-machine ssh $NODE_DATA sudo apt-get update
docker-machine ssh $NODE_DATA sudo apt-get install -y nfs-kernel-server

#
# Create workers
#
IP_NODE_DATA=$(docker-machine ip $NODE_DATA)


# backup old exports, start from scratch
docker-machine ssh $NODE_DATA  sudo cp  /etc/exports /etc/exports"_backup_"$(date '+%Y_%m_%d_%H_%M_%S')
docker-machine ssh $NODE_DATA "sudo sh -c 'echo \"\" > /etc/exports'"

for i in $N_NODES_ALL; do

  NODE=$NODE_PREFIX_$i;
  echo "Create node "$NODE

  if echo $DOCKER_MACHINES | grep $NODE ;
  then echo $NODE" already exists skip"
  else
    docker-machine create \
      --driver exoscale \
      --exoscale-api-key=$EXO_TOKEN \
      --exoscale-api-secret-key=$EXO_SECRET \
      --exoscale-availability-zone=$EXO_REGION \
      --exoscale-disk-size=10 \
      --exoscale-image=ubuntu-16.04 \
      --exoscale-instance-profile=Tiny \
      --exoscale-ssh-user=$SYS_USER \
    $NODE
  fi

  IP_NODE=$(docker-machine ip $NODE)
  docker-machine ssh $NODE sudo apt-get update
  docker-machine ssh $NODE sudo apt-get install -y nfs-common

  echo "Update firewall for "$NODE" Using ip "$IP_NODE" For host with ip "$IP_NODE_DATA
  docker-machine ssh $NODE_DATA sudo ufw allow from $IP_NODE to any port nfs

  echo "Add exports in host"
  docker-machine ssh $NODE_DATA "sudo sh -c 'echo \""$DIR_HOST" "$IP_NODE"(no_root_squash,rw,sync,no_subtree_check)\" >> /etc/exports'"

  echo "Restart nfs-kernel on host "
  docker-machine ssh $NODE_DATA sudo systemctl restart nfs-kernel-server

  if [ ! -e $DIR_WORKER_SHARED ]
  then
    docker-machine ssh $NODE sudo mkdir -p $DIR_WORKER
    echo "Mount shared dir for "$NODE
    docker-machine ssh $NODE "sudo sh -c 'mountpoint -q "$DIR_WORKER" || mount "$IP_NODE_DATA":"$DIR_HOST" "$DIR_WORKER"'"
    echo "Create shared dir for "$NODE
    docker-machine ssh $NODE sudo mkdir -p $DIR_WORKER_SHARED
    docker-machine ssh $NODE sudo chown $SYS_USER_CHOWN $DIR_WORKER_SHARED
    CMDFSTAB=$IP_NODE_DATA":"$DIR_HOST" "$DIR_WORKER" nfs auto,nofail,noatime,nolock,intr,tcp,actimeo=1800 0 0"
    docker-machine ssh $NODE_DATA "sudo sh -c 'echo \""$CMDFSTAB"\" > /etc/fstab'" 
  fi
done

#https://github.com/ContainX/docker-volume-netshare

#
# Create swarm
#

eval $(docker-machine env $NODE_MASTER)

docker swarm init --advertise-addr $(docker-machine ip $NODE_MASTER)

TOKEN=$(docker swarm join-token -q worker)
IP_NODE_MASTER=$(docker-machine ip $NODE_MASTER)

for i in $N_NODE_WORKERS; do
  eval $(docker-machine env $NODE_PREFIX_$i)
  docker swarm join --token $TOKEN $IP_NODE_MASTER:2377
done

echo "Swarm cluster has been successfuly created !";

eval $(docker-machine env $NODE_MASTER)

docker node ls