zookeeper.hcl

# Zookeeper

job "zookeeper" {
    # Specify Region
    region = "uswest-fremont"

    # Specify Datacenter
    datacenters = [ "fremont-dc1"]

    # Specify job type
    type = "service"

    # Run tasks in serial or parallel (1 for serial)
    update {
        max_parallel = 1
    }

    # define group
    group "zk-docker" {

        # define the number of times the tasks need to be executed
        count = 3

        # define job constraints
        constraint {
            attribute = "${attr.kernel.name}"
            value = "linux"
        }
        constraint {
            attribute = "${meta.zk_host_key}"
            value = "zookeeper"
        }

        # specify the number of attemtps to run the job within the specified interval
        restart {
            attempts = 10
            interval = "5m"
            delay = "25s"
            mode = "delay"
        }

        task "zk-config-dir" {
            driver = "exec"
            config {
                command = "mkdir"
                args = [ "-p", "/opt/zookeeper/config" ]
            }
        }

        task "zk-data-dir" {
            driver = "exec"
            config {
                command = "mkdir"
                args = [ "-p", "/opt/zookeeper/datadir" ]
            }
        }

        task "zookeeper" {
            driver = "docker"
            template {
                source = "/etc/nomad.d/jobs/zookeeper/templates/zoo.tpl"
                destination = "/opt/zookeeper/config/zoo.cfg"
                change_mode = "noop"
            }
            config {
                image = "<REDACTED>"
                labels {
                    group = "zk-docker"
                }
                auth {
                    username = "<REDACTED>"
                    password = "<REDACTED>"
                }
                port_map {
                    zoo_port = 2181
                    zoo_peer1 = 2888
                    zoo_peer2 = 3888
                }
                volumes = [
                    "/opt/zookeeper/config:/opt/zookeeper/conf",
                    "/opt/zookeeper/datadir:/tmp/zookeeper"
                    ]
                }
            resources {
                cpu = 100
                memory = 128
                network {
                    mbits = 10
                    port "zoo_port" {}
                    port "zoo_peer1" {}
                    port "zoo_peer2" {}
                    }
                }
            service {
                tags = ["zookeeper"]
                check {
                    type = "script"
                    name = "zookeeper_docker_check"
                    command = "/etc/consul.d/config/zk_check.sh"
                    interval = "60s"
                    timeout = "5s"
                }
            }
            }
        }
    }
And the consul template looks something like this
# The number of milliseconds of each tick
tickTime=2000
# The number of ticks that the initial
# synchronization phase can take
initLimit=10
# The number of ticks that can pass between
# sending a request and getting an acknowledgement
syncLimit=5
# the directory where the snapshot is stored.
# do not use /tmp for storage, /tmp here is just
# example sakes.
dataDir=/tmp/zookeeper
# the port at which the clients will connect
clientPort=2181
# the maximum number of client connections.
# increase this if you need to handle more clients
#maxClientCnxns=60
#
# Be sure to read the maintenance section of the
# administrator guide before turning on autopurge.
#
# http://zookeeper.apache.org/doc/current/zookeeperAdmin.html#sc_maintenance
#
# The number of snapshots to retain in dataDir
autopurge.snapRetainCount=3
# Purge task interval in hours
# Set to "0" to disable auto purge feature
autopurge.purgeInterval=4

{{range $i, $services := service "zookeeper"}}
server.{{ $i | add 1 }}={{.Address}}:2888:38888
{{ end }}