# install flannel package
$ sudo yum install flannel

$ cat /etc/sysconfig/flanneld

# Flanneld configuration options

# etcd url location.  Point this to the server where etcd runs
FLANNEL_ETCD="<your etcd server>"

# etcd config key.  This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_KEY="/coreos.com/network"

# Any additional options that you want to pass
#FLANNEL_OPTIONS=""

# Enable flanneld service by default
$ sudo systemctl enable flanneld

# start flanneld
$ sudo service flanneld start

# check if the service is running
$ sudo service flannel status

# download flannel package
$ curl -L -O https://github.com/coreos/flannel/releases/download/v0.5.5/flannel-0.5.5-linux-amd64.tar.gz

# extract the package
$ tar zxvf flannel-0.5.5-linux-amd64.tar.gz

# copy flanneld to $PATH
$ sudo cp flannel-0.5.5/flanneld /usr/local/bin

$ cat /usr/lib/systemd/system/flanneld.service
[Unit]
Description=Flanneld overlay address etcd agent
Wants=etcd.service
After=etcd.service
Before=docker.service

[Service]
Type=notify
EnvironmentFile=/etc/sysconfig/flanneld
EnvironmentFile=-/etc/sysconfig/docker-network
ExecStart=/usr/bin/flanneld -etcd-endpoints=${FLANNEL_ETCD} -etcd-prefix=${FLANNEL_ETCD_KEY} $FLANNEL_OPTIONS
Restart=on-failure

RestartSec=5s

[Install]
WantedBy=multi-user.target

#!/bin/bash

# flanneld  This shell script takes care of starting and stopping flanneld
#

# Source function library.
. /etc/init.d/functions

# Source networking configuration.
. /etc/sysconfig/network

prog=/usr/local/bin/flanneld
lockfile=/var/lock/subsys/`basename $prog`

start() {
  # Start daemon.
  echo -n $"Starting $prog: "
  daemon $prog 
    --etcd-endpoints=="<your etcd server>" 
    -ip-masq=true 
    > /var/log/flanneld.log 2>&1 &
  RETVAL=$?
  echo
  [ $RETVAL -eq 0 ] && touch $lockfile
  return $RETVAL
}

stop() {
  [ "$EUID" != "0" ] && exit 4
        echo -n $"Shutting down $prog: "
  killproc $prog
  RETVAL=$?
        echo
  [ $RETVAL -eq 0 ] && rm -f $lockfile
  return $RETVAL
}

case "$1" in
  start)
  start
  ;;
  stop)
  stop
  ;;
  status)
  status $prog
  ;;
  restart|force-reload)
  stop
  start
  ;;
  try-restart|condrestart)
  if status $prog > /dev/null; then
      stop
      start
  fi
  ;;
  reload)
  exit 3
  ;;
  *)
  echo $"Usage: $0 {start|stop|status|restart|try-restart|force-reload}"
  exit 2
esac