Install Tenable Nessus Offline

A Tenable Nessus Offline registration is suitable for computers that run Tenable Nessus, but are not connected to the internet. To ensure that Tenable Nessus has the most up-to-date plugins, Tenable Nessus servers not connected to the internet must perform these specific steps to register Nessus.

This process requires the use of two computers: the computer where you are installing Tenable Nessus, which is not connected to the internet, and another computer that is connected to the internet.

For the following instructions, we use computers A (offline Tenable Nessus server) and B (online computer) as examples.

Install Tenable Nessus

  1. During the browser portion of the Nessus installation, on the Welcome to Nessus page, select Register Offline.

  2. Click Continue.

  3. Select the Tenable Nessus type that you want to deploy: Tenable Nessus Expert, Tenable Nessus Professional, Tenable Nessus Manager, or Managed Scanner.

  4. Click Continue.

  5. (Managed Scanner only) If you select Managed Scanner, the Managed Scanner page appears.

    1. For Managed by, select the product you want to link Tenable Nessus to.

    2. For Linking Key, enter your linking key.

    3. Click Continue.

  6. A unique Challenge Code appears. In the following example, the challenge code is: aaaaaa11b2222cc33d44e5f6666a777b8cc99999.

Generate the License

  1. On a system with internet access (B), navigate to the Nessus Offline registration page.
  2. In the top field, type the challenge code shown on the Nessus Product Registration screen.

    Example challenge code: aaaaaa11b2222cc33d44e5f6666a777b8cc99999

  3. Next, where prompted, type your Tenable Nessus activation code.

    Example activation code: AB-CDE-1111-F222-3E4D-55E5-CD6F

  4. Click the Submit button.

    The offline update page appears and includes the following elements:

    • Custom URL: The custom URL displayed downloads a compressed plugins file. This file is used by Nessus to obtain plugin information. This URL is specific to your Nessus license and must be saved and used each time plugins need to be updated.
    • License: The complete text-string starting with -----BEGIN Tenable, Inc. LICENSE----- and ends with -----END Tenable, Inc. LICENSE----- is your Nessus product license information. Tenable uses this text-string to confirm your product license and registration.
    • nessus.license file: At the bottom of the web page, there is an embedded file that includes the license text-string.

    Caution: Tenable highly recommends saving the Custom URL before continuing. The URL is only shown once after registration. If you close the registration window and forget the URL, you have to restart the registration process to generate a new URL.

Download and Copy Latest Plugins

  1. While you are still using the computer with internet access (B), select the Custom URL.

    A compressed TAR file downloads.

  2. Copy the compressed TAR file to the Nessus offline (A) system.

    Use the directory specific to your operating system:




    C:\Program Files\Tenable\Nessus


    # /Library/Nessus/run/sbin/


    # /opt/nessus/sbin/


    # /usr/local/nessus/sbin/

Copy and Paste License Text

  1. While still using the computer with internet access (B), copy complete text string starting with -----BEGIN Tenable, Inc. LICENSE----- and ends with -----END Tenable, Inc. LICENSE-----.
  2. On the computer where you are installing Nessus (A), on the Nessus Product Registration screen, paste the complete text string starting with -----BEGIN Tenable, Inc. LICENSE----- and ends with -----END Tenable, Inc. LICENSE-----.
  3. Select Continue.

    Tenable Nessus finishes the installation process; this may take several minutes.

  4. Using the system administrator account you created during setup, Sign In to Tenable Nessus.