diff --git a/.gitignore b/.gitignore
index b813b11..e0c62c6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,7 @@ bin
 .idea
 .coverage
 .testrepository
+.stestr
 .tox
 *.sw[nop]
 .idea
diff --git a/hooks/ceph_hooks.py b/hooks/ceph_hooks.py
index ce7b363..1ed6d7a 100755
--- a/hooks/ceph_hooks.py
+++ b/hooks/ceph_hooks.py
@@ -91,20 +91,6 @@ STATUS_FILE = '/var/lib/nagios/cat-ceph-status.txt'
 STATUS_CRONFILE = '/etc/cron.d/cat-ceph-health'
 STORAGE_MOUNT_PATH = '/var/lib/ceph'
 
-# A dict of valid ceph upgrade paths.  Mapping is old -> new
-upgrade_paths = {
-    'cloud:trusty-juno': 'cloud:trusty-kilo',
-    'cloud:trusty-kilo': 'cloud:trusty-liberty',
-    'cloud:trusty-liberty': 'cloud:trusty-mitaka',
-}
-
-
-def pretty_print_upgrade_paths():
-    lines = []
-    for key, value in upgrade_paths.iteritems():
-        lines.append("{} -> {}".format(key, value))
-    return lines
-
 
 def check_for_upgrade():
     if not ceph.is_bootstrapped():
@@ -112,17 +98,15 @@ def check_for_upgrade():
         return
 
     c = hookenv.config()
-    old_version = c.previous('source')
+    old_version = ceph.resolve_ceph_version(c.previous('source') or
+                                            'distro')
     log('old_version: {}'.format(old_version))
     # Strip all whitespace
-    new_version = hookenv.config('source')
-    if new_version:
-        # replace all whitespace
-        new_version = new_version.replace(' ', '')
+    new_version = ceph.resolve_ceph_version(hookenv.config('source'))
     log('new_version: {}'.format(new_version))
 
-    if old_version in upgrade_paths:
-        if new_version == upgrade_paths[old_version]:
+    if old_version in ceph.UPGRADE_PATHS:
+        if new_version == ceph.UPGRADE_PATHS[old_version]:
             log("{} to {} is a valid upgrade path.  Proceeding.".format(
                 old_version, new_version))
             ceph.roll_monitor_cluster(new_version=new_version,
@@ -136,9 +120,11 @@ def check_for_upgrade():
         else:
             # Log a helpful error message
             log("Invalid upgrade path from {} to {}.  "
-                "Valid paths are: {}".format(old_version,
-                                             new_version,
-                                             pretty_print_upgrade_paths()))
+                "Valid paths are: {}".format(
+                    old_version,
+                    new_version,
+                    ceph.pretty_print_upgrade_paths()
+                ))
 
 
 @hooks.hook('install.real')
diff --git a/unit_tests/test_upgrade.py b/unit_tests/test_upgrade.py
index 5e6b8fd..ab1c8b4 100644
--- a/unit_tests/test_upgrade.py
+++ b/unit_tests/test_upgrade.py
@@ -18,6 +18,7 @@ def config_side_effect(*args):
 
 class UpgradeRollingTestCase(unittest.TestCase):
 
+    @patch('ceph_hooks.ceph.resolve_ceph_version')
     @patch('ceph_hooks.ceph.is_bootstrapped')
     @patch('ceph_hooks.log')
     @patch('ceph_hooks.ceph.roll_monitor_cluster')
@@ -30,7 +31,9 @@ class UpgradeRollingTestCase(unittest.TestCase):
                                wait_for_mons,
                                roll_monitor_cluster,
                                log,
-                               is_bootstrapped):
+                               is_bootstrapped,
+                               version):
+        version.side_effect = ['firefly', 'hammer']
         is_bootstrapped.return_value = True
         previous_mock = MagicMock().return_value
         previous_mock.previous.return_value = "cloud:trusty-juno"
@@ -39,23 +42,23 @@ class UpgradeRollingTestCase(unittest.TestCase):
         check_for_upgrade()
 
         wait_for_mons.assert_called_with(
-            new_version='cloud:trusty-kilo',
+            new_version='hammer',
             upgrade_key='admin'
         )
         roll_osd_cluster.assert_called_with(
-            new_version='cloud:trusty-kilo',
+            new_version='hammer',
             upgrade_key='admin'
         )
 
         roll_monitor_cluster.assert_called_with(
-            new_version='cloud:trusty-kilo',
+            new_version='hammer',
             upgrade_key='admin'
         )
         log.assert_has_calls(
             [
-                call('old_version: cloud:trusty-juno'),
-                call('new_version: cloud:trusty-kilo'),
-                call('cloud:trusty-juno to cloud:trusty-kilo is a valid '
+                call('old_version: firefly'),
+                call('new_version: hammer'),
+                call('firefly to hammer is a valid '
                      'upgrade path.  Proceeding.')
             ]
         )