If you set up dae as a router or other intermediate device and bind it to LAN interfaces, you need to adjust some Linux kernel parameters to make everything work fine. By default, the latest Linux distributions have IP Forwarding `disabled`. In the case where we need to up a Linux router/gateway or a VPN server or simply a plain dial-in server, then we need to enable forwarding. Moreover, in order to keep our gateway position and keep correct downstream route table, we should disable `send-redirects`. Do the followings to adjust Linux kernel parameters: