Audit Logging

Humio generates audit log events on many users actions.

These events are designed with GDPR requirements in mind and come in two variants: sensitive and non-sensitive. The purpose of the separation into these two groups is to make the audit trail trustworthy by making the sensitive actions not mutable through Humio.

Sensitive events include - assignment of roles to users on repositories - changing retention settings on repositories - deleting repositories and datasources and similar actions

and are tagged with #sensitive="true". Non-sensitive events are tagged as #sensitive="false".

All audit log events are written to the internal repository humio-audit, and to the Log4j2 logger named HUMIOAUDITLOG, which by default writes to the file ${humio.auditlog.dir}/humio-audit.log.

Retention settings for audit logs in the humio-audit repository

The repository humio-audit has special retention rules that depends on the sensitive value. Sensitive logs are deleted by retention only when they are too old, controlled by the system configuration option AUDITLOG_SENSITIVE_RETENTION_DAYS. The default is 200 years. Changing this setting requires a systems operator to change the configuration of the servers running Humio and restart Humio.

Non-sensitive logs are deleted according to the regular retention settings for the repository. The default retention settings for this repository is to keep the log for ever. Please configure according to your requirements.

Sensitive events logged

  • Create or delete a repository. Attributes include dataspaceID
  • Set Retention on a repository. Attributes include originalSizeInBytes, sizeInBytes, timeInMillis, backupAfterMillis only listing those that are set.
  • Create user
  • Update user
  • Delete user
  • Add user to a repository
  • Remove user from a repository
  • Update role for user on a repository
  • Configuration of ingest listeners
  • Adding, removing or changing ingest tokens
  • Adding, removing or changing parsers
  • Managing the cluster nodes

Non-sensitive events logged

  • Sign in to Humio. When using Auth0, this events is logged only once, when the users logs in the first time and is assigned a local uuid. When using LDAP, it is logged every time the users verifies user name / password combination.

  • Query. Every time a query is submitted on behalf of the user, either trough the UI or API using the API-token of a user. Note: Read-only dashboards are not logged here.

Permissions and ENFORCE_AUDITABLE mode

Users with Humio root role by default has both admin permissions and delete permissions in all repositories, being able to query the data stored in the repository, add and remove users, and delete data. the delete permission also allows setting retention settings on a repository. This allows users with Humio root role unrestricted access to all data in the Humio cluster.

Setting the configuration option ENFORCE_AUDITABLE=true restricts users with Humio root role as follows:

  • Root users can no longer query repository unless the user is member of the repository.
  • Root users can not set retention on repositories unless the root user has explicit delete permission on the repository.
  • Root users can not delete data from repositories unless the root user has explicit delete permission on the repository.

Regardless of value of ENFORCE_AUDITABLE Humio users with root role can always:

  • Add users to a repository and remove users from a repository, and change their permissions on the repository. This includes adding the root user it self to a repository.
  • Perform cluster related administration tasks, such as adding and deleting servers.
  • Manage ingest listeners and tokens.

Searching the events in the audit log

Special access restrictions apply. A user can get access to search the humio-audit repo using the same set of rules as any other repo. But any user who does not have access through those rules can search the repo while being restricted to searching only the events that has said user as the “actor” that did the event.