1. Go to website: https://www.tenable.com/downloads/nessus?loginAttempted=true
2. From Platform search for Linux - Debian – amd64 and download the file.
3. Agree to the License Agreement
4. Click on Checksum right next to the download button and copy the SHA256 checksum
4. Open the ~/Downloads directory in the terminal and enter the following command (change the
checksum and the Nessus version to the correct values):
echo "9b916de54b886e2a67a60ad32b5beccd7f334ab585f9fffe940a100efe3ca8c6 Nessus-10.6.3-
debian10_amd64.deb" > sha256sum_nessus
5. Run the command sha256sum –c sha256sum_nessus
6. Install Nessus by running the command: (change the Nessus version to the correct value):
sudo apt install./ Nessus-10.6.3-debian10_amd64.deb
This will install Nessus
7. You will now need to go to the following website: https://www.tenable.com/tenable-foreducation/nessus-essentials fill in your details and click Get Started.
Nessus will send u License Code to your email.
8. Open the terminal and run the command: sudo systemctl start nessusd.service
9. Enter the address https://127.0.0.1:8834 in your browser.
10. Click on Advanced. Click on Accept Risk and Continue.
11. Select Register Offline and click Continue.
12. Copy the challenge code and click on Offline Registration
13. Open your email and Copy your license code to Activate Your Nessus Essentials License
14. Copy your codes in the correct boxes and submit.
15. Copy the license code
16. Paste it under Nessus License Key and click continue.
17.Add your own username and password then click submit
18. Nessus has started
19. Go to settings. select software update
20.Click Menu Software update and select update plugin then click continue
wait tail update is complete
21. click scan and you can scan whatever you want.
you can see step by step installation with picture in this pdf file blow