How to OpenStack DevStack Setup with ZeroMQ

1)
If you are using stable havana
https://github.com/openstack-dev/devstack.git -b stable/havana

a)
Add followinf lines in localrc
===============================

##### Message Queue #####
disable_service rabbit
disable_service qpid
enable_service zeromq

##Note: Remove OFFLINE=True or set OFFLINE=False

b)
Install Dependencies
#sudo easy_install redis
or
#pip install redis

http://fosshelp.blogspot.in/2014/05/openstack-devstack-importerror-failed.html

c)
run ./stack.sh

d)
Check for the sockets cretated by ZeroMQ and confirm that ZeroMQ is running.
$ ls /var/run/openstack/
zmq_topic_cert.ubuntu 
zmq_topic_cinder-scheduler.ubuntu
zmq_topic_cinder-volume.ubuntu
zmq_topic_conductor.ubuntu

* Form nova.conf, rpc_zmq_ipc_dir = /var/run/openstack ==> (StrOpt) Directory for holding IPC sockets.

e)
Check and confirm that "zeromq" screen window exist.

f)
Location of ZeroMQ binary

/usr/local/bin/nova-rpc-zmq-receiver

g)
DevStack using following command to run ZeroMQ

$ cd /opt/stack/nova && /usr/local/bin/nova-rpc-zmq-receiver & echo $! >/opt/stack/status/stack/zeromq.pid; fg || echo "zeromq failed to start" | tee "/opt/stack/status/stack/zeromq.failure"

h)
Configure ZeroMQ
http://docs.openstack.org/trunk/config-reference/content/configuring-rpc.html