GITBOOK-146: change request with no subject merged in GitBook

contact-us/support.md

@@ -8,4 +8,42 @@ If you have any questions about Defguard or found an issue take look at these re
 * Community Support is also on [Matrix](https://matrix.to/#/#defguard:teonite.com)
 * If you would like to have our direct / enterprise support, [you can buy it from our website - there are two options: premium & enterprise.](https://defguard.net/pricing/)
 
-###
+## Things don't work, please help
+
+Before submitting your questions to our support (Matrix, direct), here are few things:
+
+1. If you have configured your defguard instance correctly, after connecting to the VPN you should be able from a client to ping your VPN server, for example if you have the following setup:
+
+<figure><img src="../.gitbook/assets/Screenshot 2024-03-24 at 18.36.43.png" alt="" width="313"><figcaption><p>Example VPN server IP</p></figcaption></figure>
+
+after connecting to VPN you should be able to ping: 10.1.1.1
+
+2. If you are not able to ping the VPN server the most common problem is that you have choosen a network that may be in conflict with your other networks (router, ...). To examine your routing use on Mac and Linux `netstat -rn` command. Let's look at the example from above, the VPN network is: 10.1.1.0/24, let's look at the network route tabile:
+
+```
+root# netstat -rn                                                                                                                                          ✔  18:40:46  
+Routing tables
+
+Internet:
+Destination        Gateway            Flags               Netif Expire
+default            10.123.123.1.      UGScg                 en0
+10.10.0/24         link#13            UCS                   en0      !
+10.0.0.0/8         link#13            UCS                   en0      !
+10.1.1.0/24        10.1.1.1.          UHLWI                 utun6  1007
+```
+
+In the example above you can see that the whole 10.0.0.0 network (with mask 255.0.0.0 eg /8) is routed through default device en0.
+
+{% hint style="danger" %}
+Because of the main routing 10.0.0.0/8 the VPN server routing the network 10.1.1.0/24 (which is included in 10.0.0.0/8) will not work.
+{% endhint %}
+
+3. Another common problem is that your server on which the gateway is working, has some firewall rules that interfere with VPN network. Please examine carefully  `ufw` and `iptables` (even if ufw is disabled there may be `iptables` rules).
+
+### Still not working, help
+
+In order to get help on a not working VPN setup to figure out what is actually wrong, please prepare the following things:
+
+1. **Routing table** of the **server** and **clien**t
+2. **Firewall rules** of the server and client
+3. Detailed information about your VPN setup - all fields (besides the keys) from the VPN configuration.