diff --git a/hooks/ceph_hooks.py b/hooks/ceph_hooks.py
index 474389a2..3dff4f06 100755
--- a/hooks/ceph_hooks.py
+++ b/hooks/ceph_hooks.py
@@ -15,6 +15,7 @@
 # limitations under the License.
 
 import base64
+from enum import Enum
 import glob
 import json
 import netifaces
@@ -25,6 +26,7 @@ import socket
 import subprocess
 import sys
 import traceback
+from typing import NamedTuple
 
 sys.path.append('lib')
 import charms_ceph.utils as ceph
@@ -386,7 +388,21 @@ def warn_if_memory_outside_bounds(value):
             "This is not recommended.", level=WARNING)
 
 
-def get_osd_memory_target():
+class OSDMemoryTargetType(Enum):
+    EMPTY = 1
+    GB = 2
+    PERCENT = 3
+    INVALID = 4
+
+
+class OSDMemoryTarget(NamedTuple):
+    # the value in bytes, as a string
+    value: str
+    # the original parsed type from the tune-osd-memory-target config value
+    parsed_type: OSDMemoryTargetType
+
+
+def get_osd_memory_target() -> OSDMemoryTarget:
     """
     Processes the config value of tune-osd-memory-target.
 
@@ -398,13 +414,16 @@ def get_osd_memory_target():
     tune_osd_memory_target = config('tune-osd-memory-target')
 
     if not tune_osd_memory_target:
-        return ""
+        return OSDMemoryTarget(value="", parsed_type=OSDMemoryTargetType.EMPTY)
 
     match = re.match(r"(\d+)GB$", tune_osd_memory_target)
     if match:
         osd_memory_target = int(match.group(1)) * 1024 * 1024 * 1024
         warn_if_memory_outside_bounds(osd_memory_target)
-        return str(osd_memory_target)
+        return OSDMemoryTarget(
+            value=str(osd_memory_target),
+            parsed_type=OSDMemoryTargetType.GB
+        )
 
     match = re.match(r"(\d+)%$", tune_osd_memory_target)
     if match:
@@ -412,11 +431,14 @@ def get_osd_memory_target():
         num_osds = len(kv().get("osd-devices", []))
         osd_memory_target = int(get_total_ram() * percentage / num_osds)
         warn_if_memory_outside_bounds(osd_memory_target)
-        return str(osd_memory_target)
+        return OSDMemoryTarget(
+            value=str(osd_memory_target),
+            parsed_type=OSDMemoryTargetType.PERCENT
+        )
 
     log("tune-osd-memory-target value invalid,"
         " leaving the OSD memory target unchanged", level=ERROR)
-    return ""
+    return OSDMemoryTarget(value="", parsed_type=OSDMemoryTargetType.INVALID)
 
 
 def get_ceph_context(upgrading=False):
@@ -539,7 +561,7 @@ def config_changed():
             relation_id=r_id,
             relation_settings={
                 'osd-host': socket.gethostname(),
-                'osd-memory-target': get_osd_memory_target(),
+                'osd-memory-target': get_osd_memory_target().value,
             }
         )
 
@@ -633,7 +655,7 @@ def prepare_disks_and_activate():
                     hookenv.config('source') or 'distro'
                 ),
                 'osd-host': socket.gethostname(),
-                'osd-memory-target': get_osd_memory_target(),
+                'osd-memory-target': get_osd_memory_target().value,
             }
         )
 
@@ -869,6 +891,11 @@ VERSION_PACKAGE = 'ceph-common'
 def assess_status():
     """Assess status of current unit"""
     # check to see if the unit is paused.
+
+    if get_osd_memory_target().parsed_type == OSDMemoryTargetType.INVALID:
+        status_set('blocked', 'tune-osd-memory-target config value is invalid')
+        return
+
     application_version_set(get_upstream_version(VERSION_PACKAGE))
     if is_unit_upgrading_set():
         status_set("blocked",
diff --git a/unit_tests/test_ceph_hooks.py b/unit_tests/test_ceph_hooks.py
index 2bfa2d3c..b83720d0 100644
--- a/unit_tests/test_ceph_hooks.py
+++ b/unit_tests/test_ceph_hooks.py
@@ -755,7 +755,8 @@ class CephHooksTestCase(unittest.TestCase):
         mock_config.side_effect = config_func
 
         target = ceph_hooks.get_osd_memory_target()
-        self.assertEqual(target, str(5 * 1024 * 1024 * 1024))  # 5GB
+        self.assertEqual(target.value, str(5 * 1024 * 1024 * 1024))  # 5GB
+        self.assertEqual(target.parsed_type, ceph_hooks.OSDMemoryTargetType.GB)
 
     @patch.object(ceph_hooks, "config")
     @patch.object(ceph_hooks, "get_total_ram")
@@ -776,7 +777,11 @@ class CephHooksTestCase(unittest.TestCase):
 
         target = ceph_hooks.get_osd_memory_target()
         # should be 50% of 16GB / 2 osd devices = 4GB
-        self.assertEqual(target, str(4 * 1024 * 1024 * 1024))  # 4GB
+        self.assertEqual(target.value, str(4 * 1024 * 1024 * 1024))  # 4GB
+        self.assertEqual(
+            target.parsed_type,
+            ceph_hooks.OSDMemoryTargetType.PERCENT
+        )
 
     @patch.object(ceph_hooks, "config")
     @patch.object(ceph_hooks, "get_total_ram")
@@ -792,7 +797,11 @@ class CephHooksTestCase(unittest.TestCase):
         mock_config.side_effect = lambda _: None
 
         target = ceph_hooks.get_osd_memory_target()
-        self.assertEqual(target, "")
+        self.assertEqual(target.value, "")
+        self.assertEqual(
+            target.parsed_type,
+            ceph_hooks.OSDMemoryTargetType.EMPTY
+        )
 
     @patch.object(ceph_hooks, "config")
     @patch.object(ceph_hooks, "get_total_ram")
@@ -812,7 +821,11 @@ class CephHooksTestCase(unittest.TestCase):
         mock_config.side_effect = config_func
 
         target = ceph_hooks.get_osd_memory_target()
-        self.assertEqual(target, "")
+        self.assertEqual(target.value, "")
+        self.assertEqual(
+            target.parsed_type,
+            ceph_hooks.OSDMemoryTargetType.INVALID
+        )
         mock_log.assert_called_with(
             "tune-osd-memory-target value invalid,"
             " leaving the OSD memory target unchanged",