PHP curl, special network interface

Question

I have a (Webserver)Server with two network interfaces. The first is the standard interface with the public internet connection, the other is a virtual VPN-networkinterface.

Now I want to send POST data via curl on an other Webservice within the VPN-Network.

How I can say the php there have to call the address with the VPN-Networkinterface?

Answer 1

The documentation lists CURLOPT_INTERFACE as a configurable option.

CURLOPT_INTERFACE The name of the outgoing network interface to use. This can be an interface name, an IP address or a host name.

curl_setopt($ch, CURLOPT_INTERFACE, "XXX.XXX.XXX.XXX");