Updated Yggdrasil (markdown)

Yggdrasil.md

@@ -1,4 +1,21 @@
-## Run using the subnet address
+Make sure you have [Yggdrasil](https://yggdrasil-network.github.io/) router installed to continue.
+
+## Host options
+
+### Main address
+
+> [!NOTE]
+> * This method requires free port `1900` for the main Yggdrasil address
+> * Keep in mind that you cannot launch a new service on the same host/port combination if it's already in use
+
+The main address is the simplest way to start using the server:
+
+``` bash
+sudo yggdrasilctl getself
+```
+* copy `IPv6 address` value e.g. `200:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx`
+
+### Subnet address
 
 > [!TIP]
 > See also `http://[222:a8e4:50cd:55c:788e:b0a5:4e2f:a92c]/yggdrasil:subnet_setting`
@@ -17,7 +34,7 @@ Create address using free `0200::/7` range, e.g. `300:xxxx:xxxx:xxxx::1`
 ```
 * this address will be reset on the next Yggdrasil service (or system) restart
 
-### Persist address settings
+#### Persist settings
 
 Add new address into `yggdrasil.service`:
 
@@ -32,7 +49,7 @@ ExecStartPost=/bin/ip address add 300:xxxx:xxxx:xxxx::1/64 dev tun0
     * `sudo systemctl restart yggdrasil`
 * check the new address is connected with `ifconfig`
 
-### Firewall
+## Firewall
 
 By using `iptables` with `ufw`, add following permission for port `1900`:
 
@@ -41,7 +58,7 @@ sudo ufw allow from 0200::/7 to 300:xxxx:xxxx:xxxx::1 port 1900 proto tcp
 ```
 * check the rules was updated successfully: `ufw status`
 
-### Launch
+## Launch
 
 Run the server from `nexy` user: