Starting the Server

Edit config/nginx.conf:

upstream unicorn {
  server unix:/tmp/unicorn.guestbook.sock fail_timeout=0;
}

server {
  client_max_body_size 4G;
  listen 80 default;
  root /home/deploy/guestbook/current/public;
  try_files $uri/index.html $uri @unicorn;
  location @unicorn {
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $http_host;
    proxy_redirect off;
    proxy_pass http://unicorn;
  }
  error_page 500 502 503 504 /500.html;
}

Edit config/unicorn.rb:

pid "/home/deploy/guestbook/current/tmp/pids/unicorn.pid"
stderr_path "/home/deploy/guestbook/current/unicorn/unicorn.log"
stdout_path "/home/deploy/guestbook/current/unicorn/unicorn.log"

listen "/tmp/unicorn.guestbook.sock"
worker_processes 2
timeout 30

Create config/unicorn_init.sh (based on the Unicorn team's example script):

#!/bin/sh
set -e
### BEGIN INIT INFO
# Provides:          unicorn
# Required-Start:    $local_fs $network
# Required-Stop:     $local_fs $network
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start/stop unicorn Rack app server
### END INIT INFO

# Example init script, this can be used with nginx, too,
# since nginx and unicorn accept the same signals.

# Feel free to change any of the following variables for your app:
TIMEOUT=${TIMEOUT-60}
APP_ROOT=/home/deploy/guestbook/current
PID=$APP_ROOT/tmp/pids/unicorn.pid
CMD="cd $APP_ROOT && bundle exec unicorn -D -c $APP_ROOT/config/unicorn.rb -E production"
INIT_CONF=$APP_ROOT/config/init.conf
UPGRADE_DELAY=${UPGRADE_DELAY-2}
action="$1"
set -u

test -f "$INIT_CONF" && . $INIT_CONF

OLD="$PID.oldbin"

cd $APP_ROOT || exit 1

sig () {
    test -s "$PID" && kill -$1 $(cat $PID)
}

oldsig () {
    test -s "$OLD" && kill -$1 $(cat $OLD)
}

case $action in
start)
    sig 0 && echo >&2 "Already running" && exit 0
    su -c "$CMD" - deploy
    ;;
stop)
    sig QUIT && exit 0
    echo >&2 "Not running"
    ;;
force-stop)
    sig TERM && exit 0
    echo >&2 "Not running"
    ;;
restart|reload)
    sig HUP && echo reloaded OK && exit 0
    echo >&2 "Couldn't reload, starting 'su -c "$CMD" - deploy' instead"
    su -c "$CMD" - deploy
    ;;
upgrade)
    if oldsig 0
    then
        echo >&2 "Old upgraded process still running with $OLD"
        exit 1
    fi

    cur_pid=
    if test -s "$PID"
    then
        cur_pid=$(cat $PID)
    fi

    if test -n "$cur_pid" &&
            kill -USR2 "$cur_pid" &&
            sleep $UPGRADE_DELAY &&
            new_pid=$(cat $PID) &&
            test x"$new_pid" != x"$cur_pid" &&
            kill -0 "$new_pid" &&
            kill -QUIT "$cur_pid"
    then
        n=$TIMEOUT
        while kill -0 "$cur_pid" 2>/dev/null && test $n -ge 0
        do
            printf '.' && sleep 1 && n=$(( $n - 1 ))
        done
        echo

        if test $n -lt 0 && kill -0 "$cur_pid" 2>/dev/null
        then
            echo >&2 "$cur_pid still running after $TIMEOUT seconds"
            exit 1
        fi
        exit 0
    fi
    echo >&2 "Couldn't upgrade, starting 'su -c "$CMD" - deploy' instead"
    su -c "$CMD" - deploy
    ;;
reopen-logs)
    sig USR1
    ;;
*)
    echo >&2 "Usage: $0 <start|stop|restart|upgrade|force-stop|reopen-logs>"
    exit 1
    ;;
esac

Connect to your server via ssh and run:

sudo rm /etc/nginx/sites-enabled/default
sudo ln -s /home/deploy/guestbook/current/config/nginx.conf /etc/nginx/sites-enabled/guestbook
sudo ln -s /home/deploy/guestbook/current/config/unicorn_init.sh /etc/init.d/unicorn_guestbook
sudo update-rc.d unicorn_guestbook defaults
sudo service nginx restart
echo 'SECRET_KEY_BASE=...' >> ~/guestbook/shared/.rbenv-vars

On your development machine, add to config/deploy.rb:

append :linked_files, ".rbenv-vars"

From your development machine's terminal, run:

bundle exec cap production deploy

Connect to your server via ssh and run:

sudo /home/deploy/guestbook/current/config/unicorn_init.sh restart

Your Rails app should now be running on your server.