First of all, I will assume that you know how to use pydevd to remote debug normal python program. If you do not know that, you can read the corresponding docs on Pycharm official website.
If you know very well how to remote debug normal python programs and you are trying to remote debug neutron, you can continue.
To remote debug neutron, only three additional things need to be done:
1. Change the worker numbers of neutron api server.
You need to edit /etc/neutron/neutron.conf to set api_worker = -1. Because by default, neutron will start multi-workers.
2. Config your IDE (my case it is PyCharm).
In Pycharm you need to set
File->Build, Extension, Debugger->Python Debuger->Gevent Compatible
3. In neutron code, You need to edit neutron/common/eventlet_utils.py
On the server, the absolute path will be the neutron install location. Like /usr/lib/python2.7/site-packages/neutron/common/eventlet_utils.py
Change the
eventlet.monkey_patch
to
eventlet.monkey_patch(os=False, thread=False)
The reason to do this is very well explained in the code comment
import os
import eventlet
def monkey_patch():
if os.name == 'nt':
# eventlet monkey patching the os and thread modules causes
# subprocess.Popen to fail on Windows when using pipes due
# to missing non-blocking IO support.
#
# bug report on eventlet:
# https://bitbucket.org/eventlet/eventlet/issue/132/
# eventletmonkey_patch-breaks
eventlet.monkey_patch(os=False, thread=False)
else:
eventlet.monkey_patch(os=False, thread=False)
OK now. You can remote debug as you did.