Most OpenStack services use the same configuration options to enable the debug logging that is also used to troubleshoot your OpenStack environment.

大多数OpenStack服务都使用相同的配置选项来启用调试日志记录，而调试日志记录也用于诊断您的OpenStack环境

To enable the debug mode for an OpenStack service:
要启用OpenStack服务的调试模式:
1、Log in to each controller node.
登录到每个控制器节点
2、Locate and open the required OpenStack service configuration file in the /etc directory, for example, /etc/nova/nova.conf.
在/etc目录中找到并打开所需的OpenStack服务配置文件，例如/etc/nova/nova.conf。
3、In the DEFAULT section, change the value for the debug parameter to True:
在默认部分，将debug参数的值更改为True:
debug = True
If the configuration file that you edit contains the use_syslog parameter, change its value to False:
如果您编辑的配置文件包含use_syslog参数，则将其值更改为False:
use_syslog = False
Disabling syslog will protect the Fuel Master node from overloading debug messages.
禁用syslog将保护Fuel Master node不重载调试消息
4、Save the changes.
保存更改
5、The following services require additional configuration to enable the debug mode:
以下服务需要额外配置才能启用调试模式:
For Cinder, edit the configuration file on each node with Cinder role.
对于cinder，在每一个有cinder角色的节点上编译配置文件

For Glance, edit two configuration files: /etc/glance/glance-api.conf and /etc/glance/glance-registry.conf.
对于glance，编辑/etc/glance/glance-api.conf和/etc/glance/glance-registry.conf两个配置文件

For Ironic, edit the /etc/nova/nova.conf file of the nova-compute service configured to work with Ironic.
对于Ironic,编辑nova-compute服务的/etc/nova/nova.conf以Ironic进行工作
6、Restart the service
重启服务

翻译官方文档：https://docs.openstack.org/fuel-docs/latest/userdocs/fuel-user-guide/troubleshooting/debug-mode.html