Update docs

README-zh.md

@@ -141,7 +141,7 @@ VPN_PASSWORD='你的VPN密码' sh vpnsetup.sh
 
 **Windows 用户** 在首次连接之前需要<a href="docs/clients-zh.md#windows-错误-809" target="_blank">修改注册表</a>，以解决 VPN 服务器 和/或 客户端与 NAT（比如家用路由器）的兼容问题。
 
-同一个 VPN 账户可以在你的多个设备上使用。但是由于 IPsec/L2TP 的局限性以及一个在 Libreswan 中的<a href="https://github.com/libreswan/libreswan/issues/166" target="_blank">问题</a>，现在还不支持同时连接在同一个 NAT（比如家用路由器）后面的多个设备。
+同一个 VPN 账户可以在你的多个设备上使用。但是由于 IPsec/L2TP 的局限性，如果需要同时连接在同一个 NAT （比如家用路由器）后面的多个设备到 VPN 服务器，你必须仅使用 <a href="docs/clients-xauth-zh.md" target="_blank">IPsec/XAuth 模式</a>。
 
 对于有外部防火墙的服务器（比如 <a href="https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-network-security.html" target="_blank">EC2</a>/<a href="https://cloud.google.com/vpc/docs/firewalls" target="_blank">GCE</a>），请为 VPN 打开 UDP 端口 500 和 4500。
 

README.md

@@ -141,7 +141,7 @@ Enjoy your very own VPN! :sparkles::tada::rocket::sparkles:
 
 For **Windows users**, this <a href="docs/clients.md#windows-error-809" target="_blank">one-time registry change</a> is required if the VPN server and/or client is behind NAT (e.g. home router).
 
-The same VPN account can be used by your multiple devices. However, due to an IPsec/L2TP limitation and an Libreswan <a href="https://github.com/libreswan/libreswan/issues/166" target="_blank">issue</a>, it is not currently possible to connect multiple devices simultaneously from behind the same NAT (e.g. home router).
+The same VPN account can be used by your multiple devices. However, due to an IPsec/L2TP limitation, if you wish to connect multiple devices simultaneously from behind the same NAT (e.g. home router), you must use only <a href="docs/clients-xauth.md" target="_blank">IPsec/XAuth mode</a>.
 
 For servers with an external firewall (e.g. <a href="https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-network-security.html" target="_blank">EC2</a>/<a href="https://cloud.google.com/vpc/docs/firewalls" target="_blank">GCE</a>), open UDP ports 500 and 4500 for the VPN.