Long: interface Arg: <name> Help: Use network INTERFACE (or address) See-also: dns-interface --- Perform an operation using a specified interface. You can enter interface name, IP address or host name. An example could look like: curl --interface eth0:1 https://www.example.com/ If this option is used several times, the last one will be used. On Linux it can be used to specify a VRF, but the binary needs to either have CAP_NET_RAW or to be ran as root. More information about Linux VRF: https://www.kernel.org/doc/Documentation/networking/vrf.txt