REASON: Unable to start PostgreSQL server. Exiting

more /var/log/ambari-server/ambari-server.log

查看日志报错为:could not translate host name “localhost”, service “5432” to address: Name or service not known
解决方法:
在/etc/hosts文件下增加如下内容：

127.0.0.1 localhost localhost.localdomain

source /etc/profile

问题解决。