diff --git a/zuul/cmd/server.py b/zuul/cmd/server.py
index 1fb4a32..5e675fd 100755
--- a/zuul/cmd/server.py
+++ b/zuul/cmd/server.py
@@ -107,7 +107,7 @@
                 jobs.add(v)
         for job in sorted(layout.jobs):
             if job not in jobs:
-                print("Job %s not defined" % job)
+                print("FAILURE: Job %s not defined" % job)
                 failure = True
         return failure