Offline Mode

You can set new or existing Tenable Nessus scanners to offline mode. Offline mode automatically disables any features that require a connection to the Tenable Nessus feed. For this reason, Tenable recommends using offline mode for any scanner that is offline or air-gapped.

Activate or Deactivate Offline Mode

  • To register Tenable Nessus in offline mode during installation, select the Register Offline option in the installation user interface.

  • To activate offline mode on an existing Tenable Nessus scanner, run nessuscli fetch --register-offline nessus.license from the command line.

  • To deactivate offline mode on an existing Tenable Nessus scanner, run nessuscli fetch --register <activation-code> from the command line.

For more information about nessuscli fetch commands, see Fetch Commands.

Offline Mode Functionality

The following features and elements are disabled in offline mode:

  • All functionality that requires connection to the Tenable Nessus feed and:

    • Core and plugin updates

    • nessuscli commands that require connection to the Tenable Nessus feed (for example, nessuscli update)

    • Feed status updates in the Events tab

    • License registration checks

  • Terrascan

  • Upgrade Assistant

  • The ability to update web application scanning images and plugins

  • The ability to update the plugin detail locale

  • (Tenable Nessus Manager) The ability to update agent profile versioning

  • The ability to link Tenable Nessus to Tenable Vulnerability Management

  • In-application product updates

  • Context-sensitive help documentation icons