ERROR: openstackclient.shell Exception raised: (python-keystoneclient 0.11.2 (/usr/local/lib/python2.7/dist-packages), Requirement.parse('python-keystoneclient>=1.1.0'), set(['python-neutronclient']))

[fpatwa]

Solution:
New version of neutron client requires updated keystone client that clashes with icehouse constraints on keystone client version.
One way to fix this is to use the older neutron client by changing the global requirements:

vi /opt/stack/requirements/global-requirements.txt
change the following line:
python-neutronclient>=2.3.4,<2.4
to:
python-neutronclient>=2.3.4,<2.3.11

Then do:
./unstack.sh
./stack.sh