docs(faq): add batch client generation script (#645)

FAQ.md

@@ -110,3 +110,17 @@ Sysctl options are at `/etc/sysctl.d/20-openvpn.conf`
 **Q:** How can I access computers the OpenVPN server's remote LAN?
 
 **A:** Add a route with the subnet of the remote network to `/etc/openvpn/server.conf` and restart openvpn. Example: `push "route 192.168.1.0 255.255.255.0"` if the server's LAN is `192.168.1.0/24`
+
+---
+
+**Q:** How can I add multiple users in one go?
+
+**A:** Here is a sample bash script to achieve this:
+
+ ```sh
+userlist=(user1 user2 user3)
+
+for i in ${userlist[@]};do
+    MENU_OPTION=1 CLIENT=$i PASS=1 ./openvpn-install.sh
+done
+```