diff --git a/etc/glance-api.conf b/etc/glance-api.conf
index edae35bac0..8cbee9626b 100644
--- a/etc/glance-api.conf
+++ b/etc/glance-api.conf
@@ -34,8 +34,11 @@ bind_host = 0.0.0.0
 # Port the bind the API server to
 bind_port = 9292
 
-# Log to this file. Make sure you do not set the same log
-# file for both the API and registry servers!
+# Log to this file. Make sure you do not set the same log file for both the API
+# and registry servers!
+#
+# If `log_file` is omitted and `use_syslog` is false, then log messages are
+# sent to stdout as a fallback.
 log_file = /var/log/glance/api.log
 
 # Backlog requests when creating socket
diff --git a/etc/glance-cache.conf b/etc/glance-cache.conf
index ae28ebcacb..134f6d7e5c 100644
--- a/etc/glance-cache.conf
+++ b/etc/glance-cache.conf
@@ -5,6 +5,11 @@
 # Show debugging output in logs (sets DEBUG log level output)
 #debug = False
 
+# Log to this file. Make sure you do not set the same log file for both the API
+# and registry servers!
+#
+# If `log_file` is omitted and `use_syslog` is false, then log messages are
+# sent to stdout as a fallback.
 log_file = /var/log/glance/image-cache.log
 
 # Send logs to syslog (/dev/log) instead of to file specified by `log_file`
diff --git a/etc/glance-registry.conf b/etc/glance-registry.conf
index 6a2f577559..ff1d24e719 100644
--- a/etc/glance-registry.conf
+++ b/etc/glance-registry.conf
@@ -11,8 +11,11 @@ bind_host = 0.0.0.0
 # Port the bind the registry server to
 bind_port = 9191
 
-# Log to this file. Make sure you do not set the same log
-# file for both the API and registry servers!
+# Log to this file. Make sure you do not set the same log file for both the API
+# and registry servers!
+#
+# If `log_file` is omitted and `use_syslog` is false, then log messages are
+# sent to stdout as a fallback.
 log_file = /var/log/glance/registry.log
 
 # Backlog requests when creating socket
diff --git a/etc/glance-scrubber.conf b/etc/glance-scrubber.conf
index d02095054f..5c5e8d4ccf 100644
--- a/etc/glance-scrubber.conf
+++ b/etc/glance-scrubber.conf
@@ -5,8 +5,11 @@
 # Show debugging output in logs (sets DEBUG log level output)
 #debug = False
 
-# Log to this file. Make sure you do not set the same log
-# file for both the API and registry servers!
+# Log to this file. Make sure you do not set the same log file for both the API
+# and registry servers!
+#
+# If `log_file` is omitted and `use_syslog` is false, then log messages are
+# sent to stdout as a fallback.
 log_file = /var/log/glance/scrubber.log
 
 # Send logs to syslog (/dev/log) instead of to file specified by `log_file`