How to manually start and stop nova-api service and debug

1)
List "nova-api" service and copy the command
#ps -aux | grep nova-api

2)
Command used to start "nova-api" service
#/usr/bin/python /usr/bin/nova-api --config-file=/etc/nova/nova.conf

3)
Stop "nova-api" service
#sudo /etc/init.d/nova-api stop

4)
Start "nova-api" service manually
#sudo /usr/bin/python /usr/bin/nova-api --config-file=/etc/nova/nova.conf

5)
Find the path of nova package
#find /usr -name nova
#cd /usr/lib/python2.7/dist-packages/nova
#ls

6)
Goto "api" directory, open a *.py file anf add debug statement.
Example:
#import pdb; pdb.set_trace()

7)
Restart "nova-api" service manually
#sudo /usr/bin/python /usr/bin/nova-api --config-file=/etc/nova/nova.conf

8)
Fire OpenStack nova CLI commands
Examples:
#nova server-list
#nova image-list