diff --git a/src/main/java/com/googlesource/gerrit/plugins/metricsreporters/GerritGraphiteReporter.java b/src/main/java/com/googlesource/gerrit/plugins/metricsreporters/GerritGraphiteReporter.java
index 6ac9db2..319ece0 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/metricsreporters/GerritGraphiteReporter.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/metricsreporters/GerritGraphiteReporter.java
@@ -118,7 +118,16 @@
   @Override
   public void start() {
     if (graphiteReporter != null) {
-      graphiteReporter.start(rate, DEFAULT_RATE_UNIT);
+      try {
+        graphiteReporter.start(rate, DEFAULT_RATE_UNIT);
+      } catch (IllegalArgumentException e) {
+        String msg = e.getMessage();
+        if ("Reporter already started".equals(msg)) {
+          log.warn(msg);
+        } else {
+          throw e;
+        }
+      }
     }
   }