diff --git a/classes/local/cli/cli_exception.php b/classes/local/cli/cli_exception.php
index c2f1b47..2b7a447 100644
--- a/classes/local/cli/cli_exception.php
+++ b/classes/local/cli/cli_exception.php
@@ -78,6 +78,11 @@ class cli_exception extends Exception {
      */
     const ERROR_PLUGIN_DISABLED = 8;
 
+    /**
+     * Moodle maintenance mode is enabled.
+     */
+    const ERROR_MAINTENANCE_MODE = 9;
+
     /**
      * cliexception constructor.
      * @param string $message An explanation of the exception.
diff --git a/classes/local/cli/finish.php b/classes/local/cli/finish.php
index e00b2fb..ee8d832 100644
--- a/classes/local/cli/finish.php
+++ b/classes/local/cli/finish.php
@@ -46,9 +46,9 @@ class finish extends clibase {
     public function generate_options() {
         // Do not provide some defaults, if cloning an outage we need to know which parameters were provided.
         $options = [
-            'help' => false,
+            'help'     => false,
             'outageid' => null,
-            'active' => false,
+            'active'   => false,
         ];
         return $options;
     }
@@ -59,9 +59,9 @@ class finish extends clibase {
      */
     public function generate_shortcuts() {
         return [
-            'h' => 'help',
+            'h'  => 'help',
             'id' => 'outageid',
-            'a' => 'active',
+            'a'  => 'active',
         ];
     }
 
@@ -75,6 +75,12 @@ class finish extends clibase {
             return;
         }
 
+        // Cannot run during CLI_MAINTENANCE mode.
+        if (CLI_MAINTENANCE) {
+            throw new cli_exception(get_string('cliinmaintenancemode', 'auth_outage'),
+                cli_exception::ERROR_MAINTENANCE_MODE);
+        }
+
         // Requires outageid or active but not both at the same time.
         $byid = !is_null($this->options['outageid']);
         $byactive = $this->options['active'];
diff --git a/lang/en/auth_outage.php b/lang/en/auth_outage.php
index d6a20f3..887b6c2 100644
--- a/lang/en/auth_outage.php
+++ b/lang/en/auth_outage.php
@@ -42,6 +42,7 @@ $string['clifinishnotongoing'] = 'Outage is not ongoing.';
 $string['clifinishparamhelp'] = 'shows parameters help.';
 $string['clifinishparamactive'] = 'finishes the currently active outage.';
 $string['clifinishparamoutageid'] = 'the id of the outage to finish.';
+$string['cliinmaintenancemode'] = 'Moodle maintenance mode is on. Use "admin/cli/maintenance.php --disable" to disable it before finishing the outage.';
 $string['cliplugindisabled'] = 'The authentication plugin \'Outage\' is disabled. Please enable it in the site administration it and try again.';
 $string['cliwaitforiterroridxoractive'] = 'You must use --outageid=# or --active parameter but not both.';
 $string['cliwaitforithelp'] = 'Waits until an outage starts.';