# Nessus Essentials

> 🔗 [Nessus](https://docs.tenable.com/Nessus.htm)
>
> 🔗 [NessusCLI](https://docs.tenable.com/nessus/Content/NessusCLI.htm)

## Install Nessus

> 🔗 **Links**
>
> * [Nessus Linux Install](https://docs.tenable.com/nessus/Content/InstallNessusLinux.htm#Download-the-Nessus-package-file.)
> * [Nessus Downloads](https://www.tenable.com/downloads/nessus)

* Download Ubuntu version with `curl` (command created from the Downloads site)

```bash
cd /tmp
curl --request GET \
  --url 'https://www.tenable.com/downloads/api/v2/pages/nessus/files/Nessus-10.8.3-debian10_amd64.deb' \
  --output 'Nessus-10.8.3-debian10_amd64.deb'
```

```bash
sudo dpkg -i Nessus-*.deb

sudo systemctl start nessusd.service

# Stop & Update Nessus:
sudo systemctl stop nessusd.service
sudo /opt/nessus/sbin/nessuscli update --all
```

* Open Nessus in a local browser
  * `https://127.0.0.1:8834/`

## Configure Nessus

🔗 [Install Nessus Essentials, Professional, Expert, or Manager](https://docs.tenable.com/nessus/Content/InstallNessusEssentialsProfessionalOrManager.htm)

* **Register for Nessus Essentials** to install Nessus Essentials
* **Get an activation** code
  * On the **Get an activation code** screen, type your name and email address.
  * Click **Email**.
  * Check your email for your free activation code.
* On the **Register Nessus** screen, type your **Activation Code**.
* Proceed with the creation of a **Nessus administrator** user account.

## Reset Nessus

### Soft

* *This command deletes all your registration information and preferences, causing Nessus to run in a non-registered state. Nessus Manager retains the same linking key after resetting.*

```bash
sudo /opt/nessus/sbin/nessuscli fix --reset
```

### Hard

* *This command resets Nessus to a fresh state, deleting all registration information, settings, data, and users.*

```bash
sudo /opt/nessus/sbin/nessuscli fix --reset-all
```

***


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