diff --git a/manifests/api.pp b/manifests/api.pp
index 74df7c9b..f3dd5939 100644
--- a/manifests/api.pp
+++ b/manifests/api.pp
@@ -36,7 +36,7 @@
 #
 #  [*log_dir*]
 #    (optional) directory to which glance logs are sent.
-#    If set to boolean false, it will not log to any directory.
+#    If set to $::os_service_default, it will not log to any directory.
 #    Defaults to undef
 #
 # [*registry_host*]
diff --git a/manifests/api/logging.pp b/manifests/api/logging.pp
index 6e9dbd22..cc6c8acd 100644
--- a/manifests/api/logging.pp
+++ b/manifests/api/logging.pp
@@ -22,7 +22,7 @@
 #
 #  [*log_dir*]
 #    (optional) Directory where logs should be stored.
-#    If set to boolean false, it will not log to any directory.
+#    If set to $::os_service_default, it will not log to any directory.
 #    Defaults to '/var/log/glance'.
 #
 #  [*log_file*]
diff --git a/manifests/cache/logging.pp b/manifests/cache/logging.pp
index c1697470..7592700e 100644
--- a/manifests/cache/logging.pp
+++ b/manifests/cache/logging.pp
@@ -22,7 +22,7 @@
 #
 #  [*log_dir*]
 #    (optional) Directory where logs should be stored.
-#    If set to boolean false, it will not log to any directory.
+#    If set to $::os_service_default, it will not log to any directory.
 #    Defaults to '/var/log/glance'
 #
 #  [*log_file*]
diff --git a/manifests/glare/logging.pp b/manifests/glare/logging.pp
index 54d28eb4..eafa4baa 100644
--- a/manifests/glare/logging.pp
+++ b/manifests/glare/logging.pp
@@ -22,7 +22,7 @@
 #
 #  [*log_dir*]
 #    (optional) Directory where logs should be stored.
-#    If set to boolean false, it will not log to any directory.
+#    If set to $::os_service_default, it will not log to any directory.
 #    Defaults to '/var/log/glance'
 #
 #  [*log_file*]
diff --git a/manifests/registry.pp b/manifests/registry.pp
index a6aa8025..607f7993 100644
--- a/manifests/registry.pp
+++ b/manifests/registry.pp
@@ -31,7 +31,7 @@
 #
 #  [*log_dir*]
 #    (optional) directory to which glance logs are sent.
-#    If set to boolean false, it will not log to any directory.
+#    If set to $::os_service_default, it will not log to any directory.
 #    Defaults to undef.
 #
 #  [*database_connection*]
diff --git a/manifests/registry/logging.pp b/manifests/registry/logging.pp
index addfec36..ccba9cae 100644
--- a/manifests/registry/logging.pp
+++ b/manifests/registry/logging.pp
@@ -22,7 +22,7 @@
 #
 #  [*log_dir*]
 #    (optional) Directory where logs should be stored.
-#    If set to boolean false, it will not log to any directory.
+#    If set to $::os_service_default, it will not log to any directory.
 #    Defaults to '/var/log/glance'.
 #
 #  [*log_file*]
diff --git a/releasenotes/notes/fix_log_dir_documentation-0e2dcaf9a5d5c58c.yaml b/releasenotes/notes/fix_log_dir_documentation-0e2dcaf9a5d5c58c.yaml
new file mode 100644
index 00000000..25e070f3
--- /dev/null
+++ b/releasenotes/notes/fix_log_dir_documentation-0e2dcaf9a5d5c58c.yaml
@@ -0,0 +1,3 @@
+---
+fixes:
+  - Fixed documentation for log_dir parameter