diff --git a/neat/globals/manager.py b/neat/globals/manager.py
index c7c3f45..9a8d00b 100644
--- a/neat/globals/manager.py
+++ b/neat/globals/manager.py
@@ -76,6 +76,7 @@ from hashlib import sha1
 import novaclient
 from novaclient.v1_1 import client
 import time
+import subprocess
 
 import neat.common as common
 from neat.config import *
@@ -159,7 +160,7 @@ def start():
         int(config['log_level']))
 
     state = init_state(config)
-    switch_hosts_on(state['compute_hosts'])
+    switch_hosts_on(state['db'], state['compute_hosts'])
 
     bottle.debug(True)
     bottle.app().state = {
@@ -675,9 +676,16 @@ def switch_hosts_off(db, sleep_command, hosts):
     :param hosts: A list of hosts to switch off.
      :type hosts: list(str)
     """
-    # TODO: implement running the sleep command over SSH
+    if sleep_command:
+        for host in hosts:
+            if log.isEnabledFor(logging.DEBUG):
+                log.debug('Calling: ssh {0} "{1}"'. \
+                              format(host, sleep_command))   
+            subprocess.call(
+                'ssh {0} "{1}"'.format(host, sleep_command), 
+                shell=True)
     if log.isEnabledFor(logging.INFO):
-        log.info('Switch off hosts: %s', str(hosts))   
+        log.info('Switched off hosts: %s', str(hosts))   
     db.insert_host_states(dict((x, 0) for x in hosts))
 
 
@@ -692,5 +700,5 @@ def switch_hosts_on(db, hosts):
      :type hosts: list(str)
     """
     if log.isEnabledFor(logging.INFO):
-        log.info('Switch on hosts: %s', str(hosts))
+        log.info('Switched on hosts: %s', str(hosts))
     db.insert_host_states(dict((x, 1) for x in hosts))
diff --git a/tests/globals/test_manager.py b/tests/globals/test_manager.py
index b8b5139..dd0e14b 100644
--- a/tests/globals/test_manager.py
+++ b/tests/globals/test_manager.py
@@ -19,6 +19,7 @@ import bottle
 from hashlib import sha1
 from novaclient.v1_1 import client
 import time
+import subprocess
 
 import neat.globals.manager as manager
 import neat.common as common
@@ -152,8 +153,10 @@ class GlobalManager(TestCase):
     def test_start(self):
         with MockTransaction:
             app = mock('app')
+            db = mock('db')
             hosts = ['host1', 'host2']
             state = {'property': 'value',
+                     'db': db,
                      'compute_hosts': hosts}
             config = {
                 'log_directory': 'dir',
@@ -167,7 +170,7 @@ class GlobalManager(TestCase):
             expect(common).init_logging('dir', 'global-manager.log', 2).once()
             expect(manager).init_state(config). \
                 and_return(state).once()
-            expect(manager).switch_hosts_on(hosts).once()
+            expect(manager).switch_hosts_on(db, hosts).once()
             expect(bottle).app().and_return(app).once()
             expect(bottle).run(host='localhost', port=8080).once()
             manager.start()
@@ -348,13 +351,23 @@ class GlobalManager(TestCase):
                 {'vm1': 512, 'vm2': 1024}
 
     def test_switch_hosts_off(self):
+        db = db_utils.init_db('sqlite:///:memory:')          
+
         with MockTransaction:
-            db = db_utils.init_db('sqlite:///:memory:')          
+            expect(subprocess).call('ssh h1 "sleep"', shell=True).once()
+            expect(subprocess).call('ssh h2 "sleep"', shell=True).once()
             expect(db).insert_host_states({
                     'h1': 0,
                     'h2': 0}).once()
             manager.switch_hosts_off(db, 'sleep', ['h1', 'h2'])
 
+        with MockTransaction:
+            expect(subprocess).call.never()
+            expect(db).insert_host_states({
+                    'h1': 0,
+                    'h2': 0}).once()
+            manager.switch_hosts_off(db, '', ['h1', 'h2'])
+
     def test_switch_hosts_on(self):
         with MockTransaction:
             db = db_utils.init_db('sqlite:///:memory:')