New guide: Tailscale VPN

docs/guides/security/tailscale_vpn.md

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+---
+title: Tailscale VPN
+author: Neel Chauhan
+contributors:
+tested_with: 9.3
+tags:
+  - security
+---
+
+# Tailscale VPN
+
+## Introduction
+
+[Tailscale](https://tailscale.com/) is a zero-config, end-to-end encrypted, peer-to-peer VPN based on Wireguard. Tailscale supports all major desktop and mobile operating systems.
+
+When compared to other VPN solutions, Tailscale does not require open TCP/IP ports and can work behind Network Address Translation or a firewall.
+
+## Prerequisites and assumptions
+
+The following are minimum requirements for using this procedure:
+
+* The ability to run commands as the root user or use `sudo` to elevate privileges
+* A Tailscale account
+
+## Installing Tailscale
+
+To install Tailscale, we first need to add its `dnf` repository (note if you are using Rocky Linux 8.x, substitute in 8):
+
+```bash
+dnf config-manager --add-repo https://pkgs.tailscale.com/stable/rhel/9/tailscale.repo
+```
+
+Then install Tailscale:
+
+```bash
+dnf install tailscale
+```
+
+## Configuring Tor
+
+With the packages installed, you need to enable and configure Tailscale. To enable the Tailscale daemon:
+
+```bash
+systemctl enable --now tailscaled
+```
+
+Subsequently, you will authenticate with Tailscale:
+
+```bash
+tailscale up
+```
+
+You will get a URL for authentication. Visit that in a browser and log into Tailscale:
+
+![Tailscale login screen](../images/tailscale_1.png)
+
+Subsequently, you will grant access to your server. Click **Connect** to do so:
+
+![Tailscale grant access dialog](../images/tailscale_2.png)
+
+When you've granted access, you will see a success dialog:
+
+![Tailscale login successful dialog](../images/tailscale_3.png)
+
+Once your server is authenticated with Tailscale, it will get a Tailscale IPv4 address:
+
+```bash
+tailscale ip -4
+```
+
+You will also get a non-routable Tailscale IPv6 address:
+
+```bash
+tailscale ip -6
+```
+
+## Conclusion
+
+Traditionally, VPN services operated in a Client-Server model where a VPN gateway was centralized. This required manual configuration, firewall configuration and giving user accounts. Tailscale solves this problem by its peer-to-peer model combined with network-level access control.