What Is Auditing?

Auditing is the collecting of data about the use of system resources. The audit data provides a record of security-related system events. This data can then be used to assign responsibility for actions that take place on a host. Successful auditing starts with two security features: identification and authentication. At each login, after a user supplies a user name and PAM authentication, a unique audit session ID is generated and associated with the user's process. The audit session ID is inherited by every process that is started during the login session. When a user switches to another user, all user actions are tracked with the same audit user ID. For more details about switching identity, see the su(1M) man page.

The audit service makes the following possible:

• Monitoring security-relevant events that take place on the host

• Recording the events in a network-wide audit trail

• Detecting misuse or unauthorized activity

• Reviewing patterns of access and the access histories of individuals and objects

• Discovering attempts to bypass the protection mechanisms

• Discovering extended use of privilege that occurs when a user changes identity