Getting "Access denied for user 'gnocchi'@'server_lab' (using password: YES)" error.

Issue

• Getting below error while executing # packstack --allinone for single node deployment:

  ERROR : Error appeared during Puppet run: 192.168.100.10_controller.pp
  Notice: /Stage[main]/Gnocchi::Db::Sync/Exec[gnocchi-db-sync]/returns: 2017-09-18 15:11:20.334 28624 CRITICAL gnocchi [-] OperationalError: (pymysql.err.OperationalError) (1045, u"Access denied for user 'gnocchi'@'server_lab' (using password: YES)")
  You will find full trace in log /var/tmp/packstack/20170918-145235-xhak4j/manifests/192.168.100.10_controller.pp.log
  Please check log file /var/tmp/packstack/20170918-145235-xhak4j/openstack-setup.log for more information
  Additional information:
   * A new answerfile was created in: /root/packstack-answers-20170918-145237.txt
   * Time synchronization installation was skipped. Please note that unsynchronized time on server instances might be problem for some OpenStack components.
   * File /root/keystonerc_admin has been created on OpenStack client host 192.168.100.10. To use the command line tools you need to source the file.
   * To access the OpenStack Dashboard browse to http://192.168.100.10/dashboard .
  Please, find your login credentials stored in the keystonerc_admin in your home directory.
  You have new mail in /var/spool/mail/root