# Tailscale VPN

The [Tailscale VPN](https://tailscale.com/) can be used to access PiKVM from the Internet
when using [port forwarding](port_forwarding.md) is not possible or does not seem secure enough.
Tailscale is a convenient and free (for private use) tool for organizing a small VPN network.

Basic Tailscale usage like whats shown below is provided as an example,
any other setting or functionality needs to be redirected to the [Tailscale support](https://tailscale.com/contact/support/).


-----
## Configuring the PiKVM

1. Install the client, run `tailscaled` service and register it in the network:

    ```
    [root@pikvm ~]# rw
    [root@pikvm ~]# pacman -Syu
    [root@pikvm ~]# pacman -S tailscale-pikvm
    [root@pikvm ~]# systemctl enable --now tailscaled
    [root@pikvm ~]# tailscale up
    ```

2. Follow the link to authorize this installation.

3. After success, perform reboot to make sure that everything is working correctly:

    ```
    [root@pikvm ~]# reboot
    ```

4. Now you can try to view the IP address of Tailscale network interface:

    ```
    [root@pikvm ~]# ip addr show tailscale0
    ```

If everything is successful, PiKVM will become a member of your VPN network.

!!! warning
    **Do not update Tailscale if you don't have access to PiKVM without VPN,
    because on breaking change in Tailscale, you may lose access.**

    Unfortunately sometimes updating the Tailscale client on PiKVM can cause problems.
    This is happening since Tailscale has weak support of read-only systems.


-----
## Configuring a client device

* [Download](https://tailscale.com/download) and install the Tailscale client for your OS
    to the system you are using (not to the system you want to control).
* Check the [admin page](https://login.tailscale.com/admin/machines) to view your VPN network.
* Follow the URL in the web browser: `https://<tailscale_kvm_ip>` and you will see PiKVM web interface.


-----
## Troubleshooting

If something not work, the usual advice is to completely remove the Tailscale from PiKVM and perform a clean installation:

```
[root@pikvm ~]# rw
[root@pikvm ~]# pacman -Rscnd tailscale
[root@pikvm ~]# rm -rf /var/lib/tailscale /var/cache/tailscale
[root@pikvm ~]# reboot
```

Next, follow this page from the beginning to install the Tailscale again.