How to Set Up OPNSense with NordVPN

OPNsense is open-source routing/firewall software that can be installed on various devices, including routers. Some routers also come with OPNsense pre-installed. Since it's backed by a very active community that quickly patches any bugs, OPNsense is known to be highly secure and efficient.

If you want to increase your router's security, you can configure NordVPN on OPNsense versions 19.1 and newer. However, its setup process can seem overwhelming at first glance, as you must manually tinker with the OPNsense settings. But fret not! It's actually very simple and straightforward.

In this article, we'll teach you how to use NordVPN on OPNsense through detailed step-by-step instructions. So, feel free to follow along.

How to Set Up OPNSense with NordVPN

To set up NordVPN on OPNsense, you first need to access OPNsense using a Web browser and then change some of its settings. Here's a step-by-step guide for it:

1. Sign up for NordVPN using its official website and your computer or mobile device.

2. Go to your NordVPN account dashboard and choose 'NordVPN' from the left bar.

3. Navigate to Advanced Settings > Set Up NordVPN Manually.

4. Pick the 'Server Recommendation' tab to choose a server. You can also click 'Advanced Filters' to sort the available servers based on different server types and supported protocols.

5. Next, navigate to Advanced Settings > Set Up NordVPN Manually > Service Credentials. You'll see your username and password here, so keep this page open.

6. Then, access OPNsense via your browser.

7. Next, navigate to System > Trust > Authorities and hit the '+Add' button.

8. Now, fill in the details mentioned below.

• Descriptive Name: The server hostname
• Method: Choose Import an existing Certificate Authority
• Certificate data: Copy the below content.

-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----

• Certificate Private Key: Leave it blank
• Serial for next certificate: Set it as default

9. Press the 'Save' button next.

10. Now, navigate to VPN > OpenVPN > Clients and click the '+Add' button.

11. Then, fill in the information mentioned below.

General Information

• Disabled: Unchecked
• Description: Enter any name
• Server mode: Choose Peer to Peer (SSL/TLS)
• Protocol: Select UDP4 (you can also use TCP4)
• Device mode: Choose tun
• Interface: Set as any
• Remote server: Leave as fault
• Host or address: The hostname of the server you're going to use
• Port: 1194 (use 443 in case you use TCP)
• Retry DNS resolution: Check the box
• Proxy host or address: Leave it blank
• Proxy port: Leave blank
• Proxy authentication extra options: Choose None

User Authentication Settings

You'll paste your NordVPN service credentials, which you copied earlier, in the User name/pass fields.

• Username: NordVPN service username
• Password: NordVPN service password

• Renegotiate time: Blank

Cryptographic Settings

• TLS Authentication: Enabled - Authentication only
• TLS Shared Key: Copy the content below and paste into this field

-----BEGIN OpenVPN Static key V1-----
e685bdaf659a25a200e2b9e39e51ff03
0fc72cf1ce07232bd8b2be5e6c670143
f51e937e670eee09d4f2ea5a6e4e6996
5db852c275351b86fc4ca892d78ae002
d6f70d029bd79c4d1c26cf14e9588033
cf639f8a74809f29f72b9d58f9b8f5fe
fc7938eade40e9fed6cb92184abb2cc1
0eb1a296df243b251df0643d53724cdb
5a92a1d6cb817804c4a9319b57d53be5
80815bcfcb2df55018cc83fc43bc7ff8
2d51f9b88364776ee9d12fc85cc7ea5b
9741c4f598c485316db066d52db4540e
212e1518a9bd4828219e24b20d88f598
a196c9de96012090e333519ae18d3509
9427e7b372d348d352dc4c85e18cd4b9
3f8a56ddb2e64eb67adfc9b337157ff4
-----END OpenVPN Static key V1-----

• Peer Certificate Authority: Choose the CA file available for your NordVPN browser
• Client Certificate: Select None (Username and Password required)
• Encryption Algorithm: AES-256-GCM
• Auth Digest Algorithm: SHA512

Tunnel Settings

• IPv4 tunnel network: Blank
• IPv6 tunnel network: Blank
• IPv4 remote network: Blank
• IPv6 remote network: Blank
• Limit outgoing bandwidth: Blank
• Compression: Legacy - Disabled LZO algorithm (--comp-lzo no)
• Type-of-service: Unchecked
• Don’t pull routes: Unchecked
• Don’t add/remove routes: Check the box

Advanced Configuration

• Advanced: Copy the below content and paste it into this section- 

remote-random;
tun-mtu 1500;
tun-mtu-extra 32;
mssfix 1450;
persist-key;
persist-tun;
reneg-sec 0;
remote-cert-tls server;

• Verbosity level: Set it to 3

12. Once done, click 'Save.'

13. Navigate to Interfaces > Assignments and click the '+' button next to New Interface.

14. Click 'OPT1' now to edit the interface.

15. Next, click 'Enable Interface' and make the following changes under General configuration:

• Description: Anything you want
• Block private networks: Unchecked
• Block bogon networks: Unchecked
• IPv4 Configuration Type: None
• IPv6 Configuration Type: None
• MAC address: Blank
• MTU: Blank
• MSS: Blank

16. No need to change the DHCP client configuration, so just click 'Save.'

17. Now, click the 'Apply changes' button.

18. Navigate to Services > Unbound DNS > General.

19. Next, fill in the details mentioned below.

• Enable: Check
• Listen port: 53
• Network Interfaces: All
• DNSSEC: Uncheck
• DHCP Registration: Check
• DHCP Domain Override: Blank
• DHCP Static Mappings: Check
• IPv6 Link-local: Unchecked
• TXT Comment Support: Unchecked
• DNS Query Forwarding: Check
• Local Zone Type: Transparent
• Custom options: Blank
• Outgoing Network Interfaces: Name your OpenVPN interface
• WPAD Records: Unchecked

20. Click the 'Save' button next and choose 'Apply changes.'

21. Navigate to Services > Unbound DNS > Advanced after that and check the following options:

• Hide Identity
• Hide Version
• Prefetch Support
• Prefetch DNS Key Support

22. Next, leave anything else at default and click Save > Apply Settings.

23. Now, move to Firewall > NAT > Outbound and choose 'Hybrid outbound NAT rule generation.'

24. Then, click on Save > Apply Changes.

25. You've to hit the '+Add' button at the top of the edit menu and choose 'Interface as NordVPN.'

26. Leave everything else at default and choose Save > Apply Changes.

27. Now, you need to move to Firewall > Rules > LAN and delete the IPv6 rule.

28. Click the edit button beside IPv4 and move to Advanced Features next.

29. Select the Gateway as the NordVPN server name next and click the Save button.

30. Click the '+Add' button and change the following: Source > LAN net and Destination > LAN Address.

31. Click the Save > Apply Changes buttons.  

32. Locate System > Settings > General and make the following changes:

• Under Networking, check the option, Prefer IPv4 over IPv6
• DNS servers:
• 103.86.96.100, Use gateway: none
• 103.86.99.100, Use gateway: none

33. For DNS server options, uncheck 'Allow DNS server list to be overridden by DHCP/PPP on WAN.'

34. Click on Save > Apply Changes.

35. Navigate to System > Gateways > Single, edit the server name, and click 'Disabled.'

36. Again, choose Save > Apply Changes.

37. Navigate to VPN > OpenVPN > Connection Status, and the service should be up.

38. Restart the connection to assign the OpenVPN Virtual Address to the interface. 

39. You can confirm that NordVPN has an IP number from Lobby > Dashboard.

40. That's all! Now NordVPN is configured on OPNsense and ready to use.

Final Thoughts

While your dashboard may look slightly different from ours, depending on your OPNsense firmware version, the general configuration is still the same. Just make sure you're using a supported version (19.1 and up) by updating your device's OPNsense version.

Along with that, if you have devices that aren't connected to your OPNsense network, you can set up NordVPN on those devices and secure them as well. This will allow you to take full advantage of the ten simultaneous device connections that NordVPN allows.

We hope this article helped you configure NordVPN on your OPNsense router. If you have any questions or wish to share your experience with us, feel free to comment below.