Hello,

I have a use case where I need to have kamailio bind to a VRF device. The configuration in question is similar to the example below, where eth1 is a slave to the VRF-lite device:

 +----------+      +-------------------+
 |   eth0   |      |    vrf-green      |
 | 1.1.1.1  |      |    127.0.0.1      |
 +----------+      +-------------------+
                            |          
                      +----------+     
                      |   eth1   |   
                      | 2.2.2.2  |  
                      +----------+

Both the main routing table and "vrf-green" routing table have a default route.

What I need to be able to do is have kamailio bind to both interfaces:

listen=eth0:5060
listen=vrf-green:5060

And additionally be able to use force_send_socket to select an interface, for example:

force_send_socket(udp:2.2.2.2:5060);

However, I can't get this to work. The above configuration fails because there is no listen directive for 2.2.2.2. Also, kamailio doesn't process packets received on the VRF with the above listen directives, it behaves as if it doesn't listen on 2.2.2.2 indeed.

In addition using either of the below:

listen=udp:2.2.2.2:5060

or
listen=eth1:5060

fails with an error upon starting kamailio.

According to the kernel documentation:

Applications that are to work within a VRF need to bind their socket to the
VRF device:

    setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, dev, strlen(dev)+1);

or to specify the output device using cmsg and IP_PKTINFO.

The question is, is VRF useable with kamailio right now? Or is development needed? Thanks!

BR,

George