Cherrypy Daemon shutdown fails - daemon

Question

I've followed the Cherrypy daemon webapp skeleton Deploying CherryPy (daemon) which is great. But I've got a shutdown problem.
The server in question is using port 8082. When the shutdown comes from the init.d script it hits the webapp-cherryd equivalent and then throws errors.
XXX#mgmtdebian7:/etc/init.d# ./XXX stop
[11/Jul/2014:09:39:25] ENGINE Listening for SIGHUP.
[11/Jul/2014:09:39:25] ENGINE Listening for SIGTERM.
[11/Jul/2014:09:39:25] ENGINE Listening for SIGUSR1.
[11/Jul/2014:09:39:25] ENGINE Bus STARTING
[11/Jul/2014:09:39:25] ENGINE Started monitor thread 'Autoreloader'.
[11/Jul/2014:09:39:25] ENGINE Started monitor thread '_TimeoutMonitor'.
[11/Jul/2014:09:39:30] ENGINE Error in 'start' listener <bound method Server.start of <cherrypy._cpserver.Server object at 0xe60e10>>
Traceback (most recent call last):
File "/usr/local/lib/python2.7/dist-packages/CherryPy-3.2.4-py2.7.egg/cherrypy/process/wspbus.py", line 197, in publish
output.append(listener(*args, **kwargs))
File "/usr/local/lib/python2.7/dist-packages/CherryPy-3.2.4-py2.7.egg/cherrypy/_cpserver.py", line 151, in start
ServerAdapter.start(self)
File "/usr/local/lib/python2.7/dist-packages/CherryPy-3.2.4-py2.7.egg/cherrypy/process/servers.py", line 168, in start
wait_for_free_port(*self.bind_addr)
File "/usr/local/lib/python2.7/dist-packages/CherryPy-3.2.4-py2.7.egg/cherrypy/process/servers.py", line 412, in wait_for_free_port
raise IOError("Port %r not free on %r" % (port, host))
IOError: Port 8080 not free on '127.0.0.1'
[11/Jul/2014:09:39:30] ENGINE Shutting down due to error in start listener:
Traceback (most recent call last):
File "/usr/local/lib/python2.7/dist-packages/CherryPy-3.2.4-py2.7.egg/cherrypy/process/wspbus.py", line 235, in start
self.publish('start')
File "/usr/local/lib/python2.7/dist-packages/CherryPy-3.2.4-py2.7.egg/cherrypy/process/wspbus.py", line 215, in publish
raise exc
ChannelFailures: IOError("Port 8080 not free on '127.0.0.1'",)
[11/Jul/2014:09:39:30] ENGINE Bus STOPPING
[11/Jul/2014:09:39:30] ENGINE HTTP Server cherrypy._cpwsgi_server.CPWSGIServer(('127.0.0.1', 8080)) already shut down
[11/Jul/2014:09:39:30] ENGINE Stopped thread '_TimeoutMonitor'.
[11/Jul/2014:09:39:30] ENGINE Stopped thread 'Autoreloader'.
[11/Jul/2014:09:39:30] ENGINE Bus STOPPED
[11/Jul/2014:09:39:30] ENGINE Bus EXITING
[11/Jul/2014:09:39:30] ENGINE Bus EXITED
XXX#mgmtdebian7:/etc/init.d#
From the surfing I've done thus far I've believe that the service is trying to restart in response to the SIGHUP signal and that it's picking up a default port of 8080 (which isn't & shouldn't be free) and therefore failing.
This leaves the service running - not what's wanted..
BTW my config that sets the port to 8082 is inside the module I load - rather than in a config file.
Thanks for any pointers in anticipation.

Answer 1

As the log clearly states CherryPy is attempting to start on 127.0.0.1:8080 and fails after 5 seconds. So you actually have a start up fail and likely it is because in my config that sets the port to 8082 is inside the module I load - rather than in a config file you don't set the port correctly and CherryPy uses default 8080.
Also I'd like to note that you shouldn't use Autoreloader in production. The cherrypy-webapp-skeleton init.d script sets production CherryPy environment which has Autoreloader off.

Answer 2

So when you do
cherrypy.tree.graph(app, "/")
you are by default creating a server instance on localhost:8080, but it doesnt actually get started until you call cherrypy.engine.start().
You are probably doing something like this
E.g. :
cherrypy.tree.graft(app, "/") # registers a server on localhost:8080
server = cherrypy._cpserver.Server() # registers a second server...
server.socket_host="0.0.0.0" # ..on 0.0.0.0 ...
server.socket_port = 5002 # ..with port 5002
server.thread_pool = 10
server.subscribe()
cherrypy.engine.start() #starts two server instances
cherrypy.engine.block()
will cause cherry py to start two server instances, one on localhost:8080, and another on 5002.
The answer is to instead do:
cherrypy.tree.graft(app, "/")
cherrypy.server.unsubscribe() # very important gets rid of default.
server = cherrypy._cpserver.Server()
server.socket_host="0.0.0.0"
server.socket_port = 5002
server.thread_pool = 10
server.subscribe()
cherrypy.engine.start() #now starts only one server instance
cherrypy.engine.block()
Your problem above is that you are staring two servers, and only one of them is falling over/erroring/closing, so port 8080 is still bound to local host and prevents a restart..