7 add some documentation about setting up systemd creds (#8)

* Update the title for the systemd part

* Add a page about the systemd-creds password registration

* Add some missing links

docs/index.md

@@ -33,3 +33,8 @@ open-source developer a product ensure itself a more stable and perennial suppor
 
 At home on your own hardware or in the cloud you trust, DuckCloud have an easy installation and its maintenance 
 process.
+
+
+[1]: https://en.wikipedia.org/wiki/Dropbox
+[2]: https://en.wikipedia.org/wiki/Microsoft_365
+[3]: https://en.wikipedia.org/wiki/Google_Drive

docs/installation-guide/introduction.md

@@ -4,7 +4,8 @@ The installation process require several steps:
 
 - [Install the binary](./packages/package-managers.md)
 - [Setup a reverse proxy](./proxies/why-use-a-proxy.md)
-- [Setup Systemd](./systemd.md)
+- [Start/Enable the systemd service](./systemd.md)
+- [Register your password to allow an automatic restart](./password.md) (optional)
 
 
 !!! example ""

docs/installation-guide/password.md

@@ -0,0 +1,63 @@
+# Register your password 
+
+
+You can let [systemd](https://systemd.io/CREDENTIALS/) and [systemd-creds](https://www.freedesktop.org/software/systemd/man/latest/systemd-creds.html) 
+handle your master password.
+
+### Why ?
+
+All the files handled by Duckcloud are encrypted with a master password provided by you. Without it Duckcloud can't function 
+properly as it can't read your files. For security reasons the master password is only kept encrypted in memory. So if the 
+server stops or your machine restarts the memory is lost and so is the ability to Duckcloud to read your files. That's why 
+you needs to give your password after each restart.
+
+This manual step can be very tedious as it make your service unoperable after each restart until an admin have put the password. That's why we
+propose a secure way to do it automatically.
+
+
+!!! danger "Security note"
+    You should register your password only if you trust your machine and the people on it. Everyone one with root access can easily seen your password in clear.
+
+
+### How ?
+
+
+#### Stop the service
+
+First you needs to stop the service:
+
+!!! Run
+    ```
+    sudo systemctl stop duckcloud.service
+    ```
+
+#### Generate the credentials:
+
+The credentials are handled by [systemd](https://systemd.io/CREDENTIALS/) and the [systemd-creds](https://www.freedesktop.org/software/systemd/man/latest/systemd-creds.html) command.
+This tooling allows to keep your password encrypted by using the [Trusted Platform Module](https://en.wikipedia.org/wiki/Trusted_Platform_Module) if available. 
+
+This command needs to be run with the root permissions:
+
+!!! Run
+    ```bash
+    systemd-ask-password -n | systemd-creds encrypt --name=password - /etc/duckcloud/password.cred
+    ```
+
+#### Enable the credentials:
+
+You need to indicate to systemd that it needs to load the credentials previously generated. For that you needs
+to uncomment a line inside `/usr/lib/systemd/system/duckcloud.service`:
+
+!!! Run
+    ```bash
+    ```
+
+
+#### Restart the service
+
+Finally you can to start again the service:
+
+!!! Run
+    ```
+    sudo systemctl start duckcloud.service
+    ```

docs/installation-guide/systemd.md

@@ -1,4 +1,4 @@
-# Systemd configuration
+# Start/Enable the systemd service
 
 
 Duckcloud lifecycle is managed by [Systemd service manager](https://systemd.io/) this bring several advantages: