You can check the status of auditing conveniently from the command line by using a tool such as curl to access the Audit Applications ReST endpoint.
For more information about curl and where to find it see this page.
To check the global status of auditing, such as what audit applications that are enabled, see this page.
While this does return the global status of the auditing framework, audit data will only be generated if the audit.alfresco-access.enabled property is true.
Auditing can also be globally enabled or disabled for Audit applications, see this page for more info.
Using JMX to control auditing
A JMX client can be used to access global properties. The properties can be modified using the JMX client. A server restart will be required for changes to properties to take effect.