Use getfqdn instead of gethostname

We need routable addresses for streaming, so make sure we use the
fqdn.

Change-Id: I43cca352eb123bb484e3d51aa242ba4258c1d51e
diff --git a/zuul/executor/server.py b/zuul/executor/server.py
index 9573a9c..ffc083f 100644
--- a/zuul/executor/server.py
+++ b/zuul/executor/server.py
@@ -1600,7 +1600,7 @@
         # TODOv3(mordred): make the executor name more unique --
         # perhaps hostname+pid.
         self.hostname = get_default(self.config, 'executor', 'hostname',
-                                    socket.gethostname())
+                                    socket.getfqdn())
         self.log_streaming_port = log_streaming_port
         self.merger_lock = threading.Lock()
         self.governor_lock = threading.Lock()
diff --git a/zuul/scheduler.py b/zuul/scheduler.py
index 164eefd..2130ede 100644
--- a/zuul/scheduler.py
+++ b/zuul/scheduler.py
@@ -214,7 +214,7 @@
     def __init__(self, config, testonly=False):
         threading.Thread.__init__(self)
         self.daemon = True
-        self.hostname = socket.gethostname()
+        self.hostname = socket.getfqdn()
         self.wake_event = threading.Event()
         self.layout_lock = threading.Lock()
         self.run_handler_lock = threading.Lock()