SO_BINDTODEVICE Failing for virtual interface

Question

I am trying to run PTPDV2 (precision timing protocol) server which binds on interface for setting up multicasting.

I have a following virtual interface

eth1:0    Link encap:Ethernet  HWaddr 00:00:50:A0:42:BD  
          inet addr:10.2.0.17  Bcast:10.2.255.255  Mask:255.255.0.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          Base address:0xa000

Now, I don't have any issues binding to a normal interface, but for any virtual interface I get a failure.

 (ptpd debug1)   09:28:12.995509  (init)  netInit
 (ptpd debug1)   09:28:12.996254  (init)  Local IP address used : 10.2.0.17 
 (ptpd error)    09:28:12.997099  (init)  failed to call SO_BINDTODEVICE on the interface (strerror: No such device)

I need some pointers to overcome this issue. Any help here is appreciated.

Answer 1

I found a workaround to this problem. But it may not be the perfect solution. I am still open for suggestions.

I observed that socket bind is successful, so the socket does get the IP address of eth1:0 . But SO_BINDTODEVICE was failing since this was a virtual interface.

So i decided to call SO_BINDTODEVICE on the real interface that is eth1, since both eth1:0 and eth1 share same MAC.

Which this, i am no longer blocked as the responses are typically unicast for me. But this may not work perfectly if some one wants multicast support on receiving too.

Open for suggestion