How to get started with WireGuard VPN

Wireguard SSH only premade firewall rules

WireGuard is a fast and modern VPN that utilizes state-of-the-art cryptography. It’s much faster than OpenVPN or IPsec while also having a smaller codebase that is easier to audit and maintain.

In this tutorial, we will set up WireGuard on Ubuntu 18.04 server and configure a firewall. WireGuard was previously only available as a DKMS kernel module but it has since been added as LKM module to the 5.6 kernel.

Try UpCloud for free! Deploy a server in just 45 seconds

Sign up with UpCloud

First things first, if you have not yet registered on UpCloud, begin by getting signed up.

Deploy a new cloud server

Deploying a new server on UpCloud is an easy and straightforward process. To get started, log into your UpCloud Control Panel and select to Deploy a server under the Servers section.

The deployment page shows a number of options for customizing a new cloud server.

  1. Choose the server location from the available data centres
  2. Pick a configuration, the $5 per month plan is a good starting point
  3. Select Ubuntu 18.04 for the operating system
  4. Add any SSH keys you want to use
  5. Give your server a hostname and description
  6. Deploy!

You can find more detailed instructions on server deployment at the UpCloud newcomer’s tutorials.

Installing WireGuard

When your new cloud server is up and running, log in using SSH.

WireGuard is now available directly from the official repositories on Ubuntu 18.04. However, before you begin installing WireGuard, make sure your system is up to date.

sudo apt-get update && sudo apt-get upgrade -y

Now we can install WireGuard itself and all of its dependencies.

sudo apt-get install wireguard

Repeat the installation steps on each client you wish to connect to the WireGuard server.

WireGuard has software for most operating systems and you can connect your Windows, Linux or macOS and Android or iOS devices easily. You can find the available packages at their download page.

With WireGuard installed, continue below with the steps to further configure your server.

IP forwarding

Next, to be able to connect through your WireGuard server, you’ll need to enable packet forwarding. This is only done on the WireGuard server and not necessary for any clients.

Open the system variables file for edit.

sudo nano /etc/sysctl.conf

Then uncomment the following line by removing the # at the beginning of the line.

net.ipv4.ip_forward=1

Once done, save the file and exit the editor.

Then apply the new option with the command below.

sudo sysctl -p
net.ipv4.ip_forward=1

If you see the option repeated like above when reloading the system variables it was enabled successfully.

Configuring firewall rules

You should also configure a firewall to block any unwanted connections and keep your server secure. You can do this by either installing a software firewall on your cloud server or by using the Firewall service at your UpCloud Control Panel.

For Ubuntu servers, you can install the ufw, the Uncomplicated Firewall, using the command below.

sudo apt install ufw

Next, add the following rules to allow SSH and WireGuard connections.

sudo ufw allow ssh
sudo ufw allow 51820/udp

Enable the firewall with the next command.

sudo ufw enable

Then confirm the command when prompted.

Command may disrupt existing ssh connections. Proceed with operation (y|n)? y

Afterwards, you can check the active firewall rules with the command below.

sudo ufw status

The other option is to use UpCloud’s L3 firewall that can be utilized to secure your WireGuard server. In order to add firewall rules open your UpCloud Control Panel and navigate to the Firewall tab in your server settings.

The easiest way to configure the firewall is to import a set of premade rules that work for our intended use case. Click to Import premade profile from the Import rules menu.

Wireguard firewall import premade profile

Then select the Only SSH allowed rule set and click the Import rules button.

Wireguard SSH only premade firewall rules

We also need to allow WireGuard connection which uses the UDP protocol and can be configured to any port. We’ll be using the port 51820 so add the following incoming traffic rule.

Wireguard add firewall rule

Once the rules have been added successfully check that the default rule is set to drop then click Save changes and Enable firewall to confirm.

Generating private and public keys

WireGuard works by encrypting the connection using a pair of cryptographic keys. The keypair is used by sharing the public key with the other party who then can encrypt their message in such a way that it can only be decrypted with the corresponding private key. To make the communication secure both ways, each party needs to have their own private and public keys as each pair only enables one-way messaging.

For the use in WireGuard, the server and each client must generate their own key pair and then exchange public keys.

To get started with generating the keys for the server change into the WireGuard directory.

cd /etc/wireguard

Next, set the permissions for the directory with the following command. Note that you need to be logged in with the root account to do this.

umask 077

Then with the required permissions set, generate a new key pair with the command below.

wg genkey | tee privatekey | wg pubkey > publickey

Repeat these steps on each client you want to connect to the WireGuard server.

Remember that you should never share your private key with anyone.

Generate server config

We are then set to start configuring the WireGuard server. The config files are generally stored in /etc/wireguard folder. Create a new configuration file called wg0.conf in that folder.

sudo nano /etc/wireguard/wg0.conf

The configuration below will make your WireGuard server accept connections to 51820 and allow a client with the public key corresponding to the private key we made above.

Add the following directives to the configuration file.

[Interface]
PrivateKey = <contents-of-server-privatekey>
Address = 10.0.0.1/24
PostUp = iptables -A FORWARD -i wg0 -j ACCEPT; iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
PostDown = iptables -D FORWARD -i wg0 -j ACCEPT; iptables -t nat -D POSTROUTING -o eth0 -j MASQUERADE
ListenPort = 51820

[Peer]
PublicKey = <contents-of-client-publickey>
AllowedIPs = 10.0.0.2/32

Note that you need to include the actual keys, a string of letters, numbers and symbols, in the configuration file. You can read the key files with the following commands.

sudo cat /etc/wireguard/publickey
sudo cat /etc/wireguard/privatekey

Then save the file and exit the editor.

Starting WireGuard and enabling it at boot

With the configuration in place, we are ready to start the server. WireGuard has a convenient wrapper called wg-quick that can be used to start new interfaces without needing to go into the setup details. You can use it to start your configuration using the following command.

wg-quick up wg0

You should see an output like below upon successfully starting the interface.

[#] ip link add wg0 type wireguard
[#] wg setconf wg0 /dev/fd/63
[#] ip -4 address add 10.0.0.1/24 dev wg0
[#] ip link set mtu 1420 up dev wg0
[#] iptables -A FORWARD -i wg0 -j ACCEPT; iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

Your WireGuard server is then running. You can check your configuration with the following command.

wg show
interface: wg0
  public key: pcDxSxSZp5x87cNoRJaHdAOzxrxDfDUn7pGmrY/AmzI=
  private key: (hidden)
  listening port: 51820

peer: gCQKfJL8Xff2MNmvceVQ0nQAmLsSM0tXClhvVNzSil4=
  allowed ips: 10.0.0.2/32

To enable WireGuard to start automatically at system boot, also enable the systemd service.

systemctl enable [email protected]

In case you get an error starting the server such as the example below.

RTNETLINK answers: Operation not supported
Unable to access interface: Protocol not supported

Make sure your server software is fully up-to-date.

sudo apt-get update && sudo apt-get upgrade -y

Then check that the WireGuard kernel module is loaded with the command below. If successful, you should not see any output.

sudo modprobe wireguard

If you get an error saying the module is missing, restart your WireGuard server and try again.

sudo reboot

When the kernel module is loaded, you can try starting WireGuard again.

Client configuration 

Once your WireGuard server is up and running, you need to configure your client device. They offer software for most operating systems to connect any of your Windows, Linux or macOS and Android or iOS devices easily. You can find available packages at their download page.

On a client computer, create a new configuration file in the /etc/wireguard directory.

sudo nano /etc/wireguard/wg0.conf

Then add the following to that file. Remember to set the client private key and server public key to their corresponding places and also include your WireGuard server’s public IP address.

[Interface]
Address = 10.0.0.2/32
PrivateKey = <contents-of-client-privatekey>
DNS = 1.1.1.1

[Peer]
PublicKey = <contents-of-server-publickey>
Endpoint = <server-public-ip>:51820
AllowedIPs = 0.0.0.0/0, ::/0

Note that setting AllowedIPs to 0.0.0.0/0, ::/0 will forward all traffic over the WireGuard VPN connection. If you want to only use WireGuard for specific destinations, set their IP address ranges in the list separated by a comma.

Once you’ve set the keys and the server address, save the file and exit the editor.

Start the connection with the command below.

sudo wg-quick up wg0

You can also use the system command to start WireGuard as a service.

sudo systemctl start [email protected]

Then when you want to disconnect, use either of the following commands depending on which method you used to start it.

sudo wg-quick down wg0
sudo systemctl stop [email protected]

WireGuard will then disconnect from the server and remove the related network settings.

Adding more clients

If you want to also use the WireGuard VPN on other devices, you can add more clients to your server. Adding clients is really simple and easy.

First, install WireGuard on your new client devices as before and create a new key pair.

Then edit the wg0.conf file on your WireGuard server.

sudo nano /etc/wireguard/wg0.conf

Add the following entry at the end of the file to include your second client’s public key and set the IP address.

[Peer]
PublicKey = <content-of-client2-publickey>
AllowedIPs = 10.0.0.3/32

Afterwards, save the file and exit the editor.

Then restart the service to update the configuration.

sudo systemctl restart [email protected]

All done! You can then connect with the new client as you did before.

Aaro Kuusela

  1. In many of the tutorials I see that the address tends to be “ 10.0.0.x” should we keep it like that or change it to “192.168.0.x” to match our networks?

    Reply
  2. This is by far the most complete Wireguard setup tutorial I’ve seen so far.

    Reply
  3. Muhammad Fazil

    Hi. How to remove a client from linux terminal? If I edit wg0.conf in server and remove the client entry, it is coming back again after the service is restarted. Do we have a command to remove the peer? I tried few commands, it says improper usage of command every time. Thank you.

    Reply
  4. Hello – Great tutorial. When I try to access my online banking, the connection is refused while on VPN. I’ve tried wireguard, shadowsocks proxy, openvpn all with same results. Is there any other tool I could use for privacy that won’t be detected by my bank? I always have to disable the VPN before I connect to my bank, and would like to avoid doing this. I use vultr’s cloud servers. My bank is bbvausa.com

    Thanks!

    Reply
  5. Hello,
    I just installed WireGuard on an LCX container using Proxmox. I created a Ubutu 18.04 machine and run all the instructions listed, but when I run the “wg-quick up wg0” command, I got the following error:
    [#] ip link add wg0 type wireguard
    Error: Unknown device type.
    Unable to access interface: Protocol not supported
    [#] ip link delete dev wg0
    Cannot find device “wg0”

    I also have another error by running:
    [email protected]:/etc/wireguard# sudo modprobe wireguard
    modprobe: FATAL: Module wireguard not found in directory /lib/modules/5.4.44-1-pve
    [email protected]:/etc/wireguard#

    How can I fix this?
    Thank you.

    Reply
  6. When I attempted to add the repo in Ubuntu 18.04 it said:

    “`$ sudo add-apt-repository ppa:wireguard/wireguard
    Cannot add PPA: ‘ppa:~wireguard/ubuntu/wireguard’.
    The team named ‘~wireguard’ has no PPA named ‘ubuntu/wireguard’
    Please choose from the following available PPAs:“`

    So I did “`sudo apt-get install wireguard“` and it installed but seems to be an old version (1.0.20200513-1~18.04.2). Current version would appear to be 1.0.20201112 from the wireguard website.

    Suggestions?

    Reply
  7. Hello,
    I already update to the least version but sitll get the same problem with Janne Ruostemaa, but i use the gcp vm with debain is that the problem let me get this error?

    [#] ip link add wg0 type wireguard
    RTNETLINK answers: Operation not supported
    Unable to access interface: Protocol not supported
    [#] ip link delete dev wg0
    Cannot find device “wg0”

    thx for your reply!

    Reply
  8. In server intereface address
    Address = 10.0.0.1/24
    I guess it should be /32

    Reply
  9. Also, I’m using ubuntu 20.04, when i run command
    net.ipv4.ip_forward=1
    i got response “net.ipv4.ip_forward=1: command not found”

    Reply
  10. Thank you for the helpful guide, everything is up and running except I want to use the DNS that’s on my server, which is connected to my home network. I’ve tried inputting the DNS IP that’s listed in my home modem/router settings, but the connection doesn’t transmit anything. Actually putting a DNS manually for the client seems to be mandatory as my connection won’t start transmitting anything without it, so it can’t seem to be configured automatically. Any ideas how I can use my home DNS on my client when using Wireguard?

    Reply
  11. I’m still quite new to this, but am very interested in using this as a possible solution for my use case.
    Could you confirm for me that this would work:

    Computer “A” has some inventory software on it, and
    Remotely Computer “B” has a client that naturally connects to that software but is not located in the same location.

    If I have a Wireguard VPN setup on a linux server, and I have both computers connect to it, will the 2 pieces of the software be able to communicate like they are on the same Local Network?

    While connected, will the computers still be able to access the internet to do (for example) a Google Search?

    Thanks for the help.

    Reply
  12. Might be worth mentioning that it’s not possible to follow these instructions to set up a VPN via a trial server https://upcloud.com/docs/free-trial/ because the firewall applied to these servers blocks the Wireguard port. (The firewall also can’t be removed.)

    Reply
  13. Hello,

    By following your tutorial, it works, but the dns will be exposed, please test your vpn connection at https://www.dnsleaktest.com/
    or
    https://dnsleak.com/

    I also tried this tutorial to avoid DNS leaking and please check the part of Configure DNS:
    https://www.ckn.io/blog/2017/11/14/wireguard-vpn-typical-setup/

    But it still not work, and no luck to me.

    I know you are expert here, is it possible to show a tutorials upon DNS configuration to avoid DNS leaking?

    Thanks so much and have a nice day.

    Reply
  14. Hey, nice tutorial.
    But my client has no internet.

    Reply
  15. how can I use this to forward a static public IP from upcloud to my home private VM lab I use when building servers and websites for clients before they get moved to upcloud for perm hosting???

    Reply
  16. Good tutorial. Two things you might want to explain better:

    – Add a note that the 10.0.0.1 & 10.0.0.2 address should not be changed or even modified to ones own IP (I did and it did not work…). Explain that they are intended to spawn a new network region or whatever.

    – “AllowedIPs to 0.0.0.0/0, ::/0” – Maybe more explanation is necessary, because I still don’t know what do do if I just want to keep the tunnel open without routing anything to it, until I for example attach qBittorrent to that device. So what should I change it to in this case.

    greetings

    Reply
  17. Thanks for the great guide!

    I had an issue where the client (my android phone) would connect to the server (`wg show` would display a latest handshake time), however, the client would have no connectivity. Turns out my server’s network card was not “eth0” (it was “ens18”), so the iptables setup in PostUp/PostDown was not getting applied. I replaced eth0 with my actual network card and it works great now!

    Reply
  18. Hi,

    Great tutorial indeed. Is there a way my Mikrotik router and the wireguard vpn can work together?

    Reply
  19. Fabianus Harry

    Hi, I had an issue of handshake won’t happen and no data is received. I used dual boot windows and ubuntu and I currently used my wireguard on ubuntu and from what I searched its all about system time issues since I get the warning of System Clock Wound Backward, but I’ve tried syncing the system clock and the handshake just won’t happen. But sometimes when I turn on my computer after several time it just works. Any idea why this is happening and how to prevent it from happening in the future?

    Reply
  20. In linux how to configure routes to pass data through wireguard tunnel ??

    Also how to configure routes to pass through wireguard vpn client??

    Reply
  21. Tnx for the guide! Worked like a charm! it was really easy to understand after doing a few connections, keep up the good work!

    Reply
  22. Is there a way to have multiple wg interfaces, so that I could use them as vlan interfaces? Scenerio: I have different wireguard clients connecting to my wireguard server and I need a way to tag their traffic to place them on different vlans. The wireguard server will be connected to a trunk port on a switch.

    Reply
  23. Hi,
    Firstly thanks for the great tutorial.

    I’m having an issue however with the wireguard server where it doesn’t seem to be sending any data :(

    “wg show” says that data is being received on the server-side but no data is being sent in return.

    Double-checked the configuration and all seems to be fine.

    Was just wondering what your input is regarding this issue as I seem to be stuck and can’t find any relevant answers online either.

    Any help would be greatly appreciated :)

    Regards,
    John

    Reply
  24. HI, Thanks for the great tutorial, I am trying to integrate wireguard with my ios app. Problem is we need to set different allowed IP for every Peer in wg0.conf (server config file). If we add manual entry in wg0.conf file then its ok we can add by incrementing allowed IP by one for newly added Peer. But in my case I have to do this programmatically. Is there any dynamic way to solve this problem? any recommendation as best practice from your side ?
    Thanks again for the wonderful guide :)

    Reply
  25. I have installed wireguard VPN on ec2 instance (Ubuntu server), for first few months it was working fine, however, from past few days, I am getting slow connection and connectivity timed out issue.

    Reply
  26. I don’t understand it … but I set the server wg.conf and the conf file on my phone as per above and it just worked … thank you!

    Reply
  27. Hello,
    I’ve done everything that the tutorial said and checked if wg is working. Everything seems to be fine on paper, but any IP-checking website exposes my real IP. My computer also fails the DNS leak test. The only weird thing I’ve noticed is that when I run “wg show” it only shows public key, private key and listening port, and doesn’t add the [Peer] block. I would be grateful if you could help me.

    Reply
  28. I already make a wireguard server with ubuntu, but when client connect devices client can connect to the wireguard server but cannot connect to internet, how can i fix that ?

    Reply

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top