How to fix devstack stack.sh nova-api did not start

Solved How to fix devstack stack.sh nova-api did not start

Solution
======
First run ./unstack.sh
Then run ./stack.sh

This way i could bypass following Error

Error
====
+ screen -S stack -p n-api -X stuff 'cd /opt/stack/nova &&
/usr/local/bin/nova-a'i || touch
"/opt/stack/status/stack/n-api.failure"
+ echo 'Waiting for nova-api to start...'
Waiting for nova-api to start...
+ wait_for_service 60 http://192.168.1.5:8774
+ local timeout=60
+ local url=http://192.168.1.5:8774
+ timeout 60 sh -c 'while ! http_proxy= https_proxy= curl -s
http://192.168.1.5:8774 >/dev/null; do sleep 1; done'
+ die 545 'nova-api did not start'
+ local exitcode=0
+ '[' 0 == 0 ']'
+ exitcode=1
+ set +o xtrace
[ERROR] ./stack.sh:545 nova-api did not start
saju@saju-ops:~/devstack$

Success Screen
============