Hi Now I try to install ceilometer in single host, and report the error ERROR : Error appeared during Puppet run: 172.18.1.18_ceilometer.pp Error: Could not set groups on user[ceilometer]: Execution of '/usr/sbin/usermod -G ceilometer,nobody,nova ceilometer' returned 6: usermod: group 'nova' does not exist You will find full trace in log /var/tmp/packstack/20140121-012827-4t48Fn/manifests/172.18.1.18_ceilometer.pp.log I check the log show ^[[1;31mError: Could not set groups on user[ceilometer]: Execution of '/usr/sbin/usermod -G ceilometer,nobody,nova ceilometer ' returned 6: usermod: group 'nova' does not exist ^[[0m ^[[1;31mError: /Stage[main]/Ceilometer/User[ceilometer]/groups: change from nobody,ceilometer to ceilometer,nobody,nova faile d: Could not set groups on user[ceilometer]: Execution of '/usr/sbin/usermod -G ceilometer,nobody,nova ceilometer' returned 6 : usermod: group 'nova' does not exist seem this is RDO bug ? -- Shake Chen