Setup Nomad cluster on Alpine Linux on Vultr (1st boot script)

setup-vultr-alpine-nomad-cluster.sh

#!/bin/bash

# 1. Setup base dependencies

apk update
apk del ufw
apk add htop busybox-extras

# 2. Disable Swap

swapoff -a
sed -i "/swapfile/d" /etc/fstab
rm /swapfile

# 3. Install Nomad + Docker + Consul

apk add nomad
rc-update add nomad default

apk add consul
rc-update add consul default

if [[ $(hostname) = nomad-cluster-client-* ]]; then
  apk add docker
  rc-update add docker default
fi

# 4. Export environment variables

export NOMAD_CLUSTER_REGION="global"
export NOMAD_CLUSTER_DATACENTER="vultr-par"

export NOMAD_CLUSTER_NODE_SELF="{{ GetInterfaceIP \\\"eth1\\\" }}"
export NOMAD_CLUSTER_SERVER_1="10.24.96.3"
export NOMAD_CLUSTER_SERVER_2="10.24.96.4"
export NOMAD_CLUSTER_SERVER_3="10.24.96.5"

export CONSUL_CLUSTER_DATACENTER=${NOMAD_CLUSTER_DATACENTER}

export CONSUL_CLUSTER_NODE_SELF=${NOMAD_CLUSTER_NODE_SELF}
export CONSUL_CLUSTER_SERVER_1=${NOMAD_CLUSTER_SERVER_1}
export CONSUL_CLUSTER_SERVER_2=${NOMAD_CLUSTER_SERVER_2}
export CONSUL_CLUSTER_SERVER_3=${NOMAD_CLUSTER_SERVER_3}

export CONSUL_CLUSTER_CLIENT_LOCAL="127.0.0.1"

export CONSUL_CLUSTER_ENCRYPT_KEY="XXXXXXX"

# 5. Configure Consul

rm /etc/consul/*
touch /etc/consul/server.hcl
chmod 640 /etc/consul/server.hcl
chown consul:consul -R /etc/consul/

if [[ $(hostname) = nomad-cluster-server-* ]]; then
  cat << EOF > /etc/consul/server.hcl
datacenter           = "${CONSUL_CLUSTER_DATACENTER}"

data_dir             = "/var/consul"

disable_update_check = true
enable_syslog        = false

bind_addr            = "${CONSUL_CLUSTER_NODE_SELF}"
advertise_addr       = "${CONSUL_CLUSTER_NODE_SELF}"
client_addr          = "${CONSUL_CLUSTER_CLIENT_LOCAL}"

server               = true
bootstrap_expect     = 3
encrypt              = "${CONSUL_CLUSTER_ENCRYPT_KEY}"

retry_join = [
  "${CONSUL_CLUSTER_SERVER_1}",
  "${CONSUL_CLUSTER_SERVER_2}",
  "${CONSUL_CLUSTER_SERVER_3}"
]

ui_config {
  enabled = false
}
EOF
else
  cat << EOF > /etc/consul/server.hcl
datacenter           = "${CONSUL_CLUSTER_DATACENTER}"

data_dir             = "/var/consul"

disable_update_check = true
enable_syslog        = false

bind_addr            = "${CONSUL_CLUSTER_NODE_SELF}"
advertise_addr       = "${CONSUL_CLUSTER_NODE_SELF}"
client_addr          = "${CONSUL_CLUSTER_CLIENT_LOCAL}"

encrypt              = "${CONSUL_CLUSTER_ENCRYPT_KEY}"

retry_join = [
  "${CONSUL_CLUSTER_SERVER_1}",
  "${CONSUL_CLUSTER_SERVER_2}",
  "${CONSUL_CLUSTER_SERVER_3}"
]
EOF
fi

# 6. Configure Nomad

if [[ $(hostname) = nomad-cluster-server-* ]]; then
  cat << EOF > /etc/nomad.d/server.hcl
region               = "${NOMAD_CLUSTER_REGION}"
datacenter           = "${NOMAD_CLUSTER_DATACENTER}"

data_dir             = "/var/lib/nomad"
plugin_dir           = "/usr/lib/nomad/plugins"

disable_update_check = true
enable_syslog        = false

addresses {
  http = "0.0.0.0"
  rpc  = "${NOMAD_CLUSTER_NODE_SELF}"
  serf = "${NOMAD_CLUSTER_NODE_SELF}"
}

advertise {
  http = "${NOMAD_CLUSTER_NODE_SELF}"
  rpc  = "${NOMAD_CLUSTER_NODE_SELF}"
  serf = "${NOMAD_CLUSTER_NODE_SELF}"
}

server {
  enabled          = true
  bootstrap_expect = 3

  server_join {
    retry_join = [
      "${NOMAD_CLUSTER_SERVER_1}",
      "${NOMAD_CLUSTER_SERVER_2}",
      "${NOMAD_CLUSTER_SERVER_3}"
    ]
    retry_max      = 0
    retry_interval = "5s"
  }
}

consul {
  address = "${CONSUL_CLUSTER_CLIENT_LOCAL}:8500"
}

ui {
  enabled = true
}
EOF
else
  cat << EOF > /etc/nomad.d/server.hcl
region               = "${NOMAD_CLUSTER_REGION}"
datacenter           = "${NOMAD_CLUSTER_DATACENTER}"

data_dir             = "/var/lib/nomad"
plugin_dir           = "/usr/lib/nomad/plugins"

disable_update_check = true
enable_syslog        = false

addresses {
  http = "0.0.0.0"
  rpc  = "${NOMAD_CLUSTER_NODE_SELF}"
  serf = "${NOMAD_CLUSTER_NODE_SELF}"
}

advertise {
  http = "${NOMAD_CLUSTER_NODE_SELF}"
  rpc  = "${NOMAD_CLUSTER_NODE_SELF}"
  serf = "${NOMAD_CLUSTER_NODE_SELF}"
}

server {
  enabled = false
}

client {
  enabled = true

  servers = [
    "${NOMAD_CLUSTER_SERVER_1}",
    "${NOMAD_CLUSTER_SERVER_2}",
    "${NOMAD_CLUSTER_SERVER_3}"
  ]

  options = {
    "driver.allowlist" = "docker"
  }
}

consul {
  address = "${CONSUL_CLUSTER_CLIENT_LOCAL}:8500"
}

plugin "docker" {
  config {
    volumes {
      enabled = true
    }
  }
}
EOF
fi

# 7. Reboot

reboot now