Getting 502/500 Error after upgrade from 7.3.2 to 7.4.0

After I upgraded from 7.3.2 to 7.4.0, I am getting 502/500 Error

First it comes as 502 for couple of minutes and later the error turns into 500

Steps I followed Stopped GitLab Server by

sudo gitlab-ctl stop

Updgraded using following command

sudo dpkg -i gitlab_7.4.0-omnibus-1_amd64.deb

Reconfigured GitLab server

sudo gitlab-ctl reconfigured

After this, I again restarted gitlab-ctl

sudo gitlab-ctl restart

Operating System: Ubuntu 12.04 LTS

Please let me know if any logs I can provide for better debug