[feature] check redis auth failed
diff --git a/system/libraries/Cache/drivers/Cache_redis.php b/system/libraries/Cache/drivers/Cache_redis.php
index a35fbf6..d976436 100644
--- a/system/libraries/Cache/drivers/Cache_redis.php
+++ b/system/libraries/Cache/drivers/Cache_redis.php
@@ -302,7 +302,11 @@
 
 		if (isset($config['password']))
 		{
-			$this->_redis->auth($config['password']);
+			if ( ! $this->_redis->auth($config['password']))
+			{
+				log_message('debug', 'Cache: Redis authentication failed.');
+				return FALSE;
+			}
 		}
 
 		// Initialize the index of serialized values.