diff --git a/Readme.md b/Readme.md
index 1254e9c6..a0902d33 100644
--- a/Readme.md
+++ b/Readme.md
@@ -35,7 +35,8 @@ Here are the configuration properties:
 * `accessKey`: API AccessKey value (if not using IAM profile)
 * `secretKey`: API SecretKey value (if not using IAM profile)
 * `endpoint` - the URL of the AWS **endpoint** to use, or blank for the default endpoint (see [Amazon EC2 Regions and Endpoints](http://docs.aws.amazon.com/general/latest/gr/rande.html#ec2_region))
-* `refreshInterval`: Time in seconds used as minimum interval between calls to the AWS API. (default 30)
+* `synchronousLoad`: Do not use internal async loading behavior. (boolean, default: true)
+* `refreshInterval`: Unless using Synchronous Loading, time in seconds used as minimum interval between calls to the AWS API. (default 30)
 * `filter` A set of ";" separated query filters ("$Name=$Value") for the AWS EC2 API, see below.
 * `runningOnly`: if "true", automatically filter the * instances by "instance-state-name=running"
 * `useDefaultMapping`: if "true", base all mapping definitions off the default mapping provided.
@@ -44,6 +45,10 @@ Here are the configuration properties:
 
 If you leave `accessKey` and `secretKey` blank, the EC2 IAM profile will be used.
 
+Note: Rundeck 2.6.3+ uses an asynchronous nodes cache by
+default. You should enable `synchronousLoad` if you are using the
+rundeck nodes cache, or set the `refreshInterval` to 0.
+
 ## Filter definition
 
 The syntax for defining filters uses `$Name=$Value[;$Name=$value[;...]]` for any of the allowed filter names (see [DescribeInstances][1] for the available filter Names).  *Note*: you do not need to specify `Filter.1.Name=$Name`, etc. as described in the EC2 API documentation, this will handled for you.  Simply list the Name = Value pairs, separated by `;`.
diff --git a/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSource.java b/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSource.java
index 67fe6c5f..af914e2e 100644
--- a/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSource.java
+++ b/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSource.java
@@ -40,6 +40,8 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 
+import static com.dtolabs.rundeck.plugin.resources.ec2.EC2ResourceModelSourceFactory.SYNCHRONOUS_LOAD;
+
 /**
  * EC2ResourceModelSource produces nodes by querying the AWS EC2 API to list instances.
  * <p/>
@@ -186,6 +188,7 @@ public EC2ResourceModelSource(final Properties configuration) {
             clientConfiguration.setProxyUsername(httpProxyUser);
             clientConfiguration.setProxyPassword(httpProxyPass);
         }
+        queryAsync = !("true".equals(configuration.getProperty(SYNCHRONOUS_LOAD)) || refreshInterval <= 0);
         
         initialize();
     }
diff --git a/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSourceFactory.java b/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSourceFactory.java
index 7eb7de00..8a7d9c5b 100644
--- a/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSourceFactory.java
+++ b/src/main/java/com/dtolabs/rundeck/plugin/resources/ec2/EC2ResourceModelSourceFactory.java
@@ -62,6 +62,7 @@ public class EC2ResourceModelSourceFactory implements ResourceModelSourceFactory
     public static final String ROLE_ARN = "assumeRoleArn";
     public static final String MAPPING_FILE = "mappingFile";
     public static final String REFRESH_INTERVAL = "refreshInterval";
+    public static final String SYNCHRONOUS_LOAD = "synchronousLoad";
     public static final String USE_DEFAULT_MAPPING = "useDefaultMapping";
     public static final String HTTP_PROXY_HOST = "httpProxyHost";
     public static final String HTTP_PROXY_PORT = "httpProxyPort";
@@ -107,8 +108,18 @@ public ResourceModelSource createResourceModelSource(final Properties properties
                             null
                     )
             )
-            .property(PropertyUtil.integer(REFRESH_INTERVAL, "Refresh Interval",
-                    "Minimum time in seconds between API requests to AWS (default is 30)", false, "30"))
+                                                .property(PropertyUtil.bool(
+                                                        SYNCHRONOUS_LOAD,
+                                                        "Synchronous Loading",
+                                                        "Do not use internal async loading behavior.\n\n" +
+                                                        "Note: Rundeck 2.6.3+ uses an asynchronous nodes cache by " +
+                                                        "default. You should enable this if you are using the " +
+                                                        "rundeck nodes cache.",
+                                                        false,
+                                                        "true"
+                                                ))
+            .property(PropertyUtil.integer(REFRESH_INTERVAL, "Async Refresh Interval",
+                    "Unless using Synchronous Loading, minimum time in seconds between API requests to AWS (default is 30)", false, "30"))
             .property(PropertyUtil.string(FILTER_PARAMS, "Filter Params", "AWS EC2 filters", false, null))
             .property(PropertyUtil.string(ENDPOINT, "Endpoint", "AWS EC2 Endpoint, or blank for default", false, null))
             .property(PropertyUtil.string(HTTP_PROXY_HOST, "HTTP Proxy Host", "HTTP Proxy Host Name, or blank for default", false, null))