Use container hostname instead of container name

net-dhcp/network.py

@@ -91,10 +91,10 @@ def await_endpoint_container_iface(n, e, timeout=5):
         raise NetDhcpError('Timed out waiting for container to become availabile')
     return iface
 
-def endpoint_container_name(n, e):
-    for info in client.networks.get(n).attrs['Containers'].values():
+def endpoint_container_hostname(n, e):
+    for cid, info in client.networks.get(n).attrs['Containers'].items():
         if info['EndpointID'] == e:
-            return info['Name']
+            return client.containers.get(cid).attrs['Config']['Hostname']
     return None
 
 @app.route('/NetworkDriver.GetCapabilities', methods=['POST'])
@@ -350,7 +350,7 @@ class ContainerDHCPManager:
     def run(self):
         try:
             iface = await_endpoint_container_iface(self.network, self.endpoint)
-            hostname = endpoint_container_name(self.network, self.endpoint)
+            hostname = endpoint_container_hostname(self.network, self.endpoint)
 
             self.dhcp = udhcpc.DHCPClient(iface, event_listener=self._on_event, hostname=hostname)
             logger.info('Starting DHCPv4 client on %s in container namespace %s', iface['ifname'], \