Add Tailscale Documentation

src/.vuepress/config.js

@@ -135,6 +135,7 @@ module.exports = {
                   collapsable: true,
                   children: [
                     'node/securing-your-node',
+                    'node/tailscale'
                   ]
                 },
                 {

src/guides/node/tailscale.md

@@ -0,0 +1,140 @@
+# Configuring a Tailscale VPN Server
+
+::: tip NOTE
+This is **optional.**
+You only need to consider this section if you run a node at home and would like to connect to it from outside of your home network.
+:::
+
+If you would like to log into your home network remotely, such as while on vacation or on a business trip, the most common route is to use a **Virtual Private Network** server.
+This will allow you to connect to your node via SSH **and** monitor your Graphana dashboard from anywhere in the world, all without exposing your SSH port to the internet. 
+
+Many Rocket Pool node operators use [Tailscale]((https://tailscale.com/blog/how-tailscale-works/)) as their VPN server of choice for this.
+Tailscale is an open source P2P VPN tunnel and hosted endpoint discovery service.
+It takes care of authentication, publication, and the NAT traversal required to establish an end-to-end encrypted path between your machine and your node without sending any sensitive traffic to a centralized server.
+It is a very powerful tool.
+
+We will briefly cover a basic configuration of it, but feel free to [review their documentation](https://tailscale.com/kb/start/) for more details.
+
+
+## Setting Tailscale Up
+
+First, create a free [Tailscale account](https://tailscale.com/).
+Tailscale requires the use of an SSO identity provider such as Google, GitHub, Okta, Microsoft, etc.
+For details, visit [their SSO Page](https://tailscale.com/kb/1013/sso-providers/).
+
+It is recommended that you enable 2FA (Two Factor Authentication) on whichever identity provider you choose for added security.
+
+Next, follow [their onboarding guide](https://tailscale.com/kb/1017/install/) to install Tailscale on your **client** - the machine you want to connect to your network with.
+For example, this could be a laptop or your phone.
+**Note that it is *not* your Rocket Pool node!** 
+
+Once completed you should see your computer as 'connected' on the [Tailscale dashboard](https://login.tailscale.com/admin/machines).
+
+<center>
+
+![](./images/tailscale-dashboard-client.png)
+
+</center>
+
+Now, install Tailscale on your **Rocket Pool node**.
+You can find instructions for this on their website; for example, here are the [installation instructions for Ubuntu](https://tailscale.com/kb/1039/install-ubuntu-2004/).
+
+::: warning NOTE
+If you have UFW configured, you will also want to follow the [UFW Configuration Instructions](https://tailscale.com/kb/1077/secure-server-ubuntu-18-04/)).
+:::
+
+First, add Tailscale’s package signing key and repository **on your Rocket Pool node**:
+
+```shell
+curl -fsSL https://pkgs.tailscale.com/stable/ubuntu/focal.noarmor.gpg | sudo tee /usr/share/keyrings/tailscale-archive-keyring.gpg >/dev/null
+curl -fsSL https://pkgs.tailscale.com/stable/ubuntu/focal.tailscale-keyring.list | sudo tee /etc/apt/sources.list.d/tailscale.list
+```
+
+Now, install Tailscale **on your Rocket Pool node**:
+
+```shell
+sudo apt-get update
+sudo apt-get install tailscale
+```
+
+Finally, authenticate and connect your machine to your Tailscale network **on your Rocket Pool node**:
+
+```shell
+sudo tailscale up
+```
+
+You’re connected!
+You can find your Tailscale IPv4 address by running:
+
+```shell
+tailscale ip -4
+```
+
+You should now see your node machine added to the on the [Tailscale dashboard](https://login.tailscale.com/admin/machines).
+You may also change the name of the **node machine** through the dashboard, e.g. to `rocketnode`.
+
+![](./images/tailscale-dashboard-servers.png)
+
+It is suggested to [disable key expiry](https://tailscale.com/kb/1028/key-expiry) for the node machine to prevent the need to periodically re-authenticate.
+
+::: tip Note
+If you would like to access your node using a memorable hostname such as rocketnode, you can do so by enabling MagicDNS in the Tailscale settings.
+:::
+
+You should now be able to `exit` the SSH session to your node on your client, and SSH into your node again through Tailscale using `ssh your.user@rocketnode`.
+
+::: warning NOTE
+If you modified the SSH port of the **node machine** in `/etc/ssh/sshd_config` when you first configured it, use `ssh your.user@rocketnode -p <your port>` instead.
+
+For example, if you assigned SSH to port 1234, you would do:
+```
+ssh your.user@rocketnode -p 1234
+```
+:::
+
+You can now also visit `http://rocketnode:3100` in your web browser to access your Grafana dashboard from your **client**.
+
+If you have UFW configured, you can now add a rule to accept any incoming SSH connections over Tailscale.
+
+::: danger WARNING
+The following steps will modify your firewall rules.
+**You must have at least 2 SSH sessions open to your node machine before proceeding - one for modifying the configuration and testing it afterwards, and one that will stay logged in as a backup in case your changes break SSH so you can revert them!
+:::
+
+**Run these commands on the node machine.**
+
+Allow access to all incoming ssh connections over Talscale.
+
+```shell
+sudo ufw allow in on tailscale0
+```
+
+You may also remove access to the SSH port adding from the [enabling a firewall](securing-your-node.md#essential-enable-a-firewall) steps to competely lock down your node.
+Note that you **will not** be able to login from the local network as tailscale will become the only way to login.
+Only run the following command if you are okay with this.
+
+```shell
+sudo ufw delete "22/tcp"
+```
+
+Once you’ve set up firewall rules to restrict all non-Tailscale connections, restart UFW and SSH:
+
+```shell
+sudo ufw reload
+sudo service ssh restart
+```
+
+Now, confirm that everything is working as expected.
+`exit` from one of your current SSH sessions (**but remember to keep the second one open as a backup**).
+
+Next, connect to the **node machine** via SSH using the Tailscale IP address:
+
+```shell
+ssh your.user@rocketnode
+```
+
+If it works, you did everything right and can now safely log into your home network while abroad!
+
+::: tip TIP
+If you've previously port forwarded your node's SSH port in your router, you can now remove it.
+:::