When stopping NFS Gateway the following error is thrown in the NFS gateway role logs.
2017-08-17 18:09:16,529 ERROR org.apache.hadoop.oncrpc.RpcProgram: Unregistration failure with localhost:2049, portmap entry: (PortmapMapping-100003:3:6:2049)
2017-08-17 18:09:16,531 WARN org.apache.hadoop.util.ShutdownHookManager: ShutdownHook 'NfsShutdownHook' failed, java.lang.RuntimeException: Unregistration failure
java.lang.RuntimeException: Unregistration failure
Caused by: java.net.SocketException: Socket is closed
at java.net.DatagramSocket.send(DatagramSocket.java:641)
at org.apache.hadoop.oncrpc.SimpleUdpClient.run(SimpleUdpClient.java:62)
Checking rpcinfo -p : the following entry is still there:
" 100003 3 tcp 2049 nfs"