title: SO_BINDTODEVICE Failing for virtual interface
body: <p>I am trying to run PTPDV2 (precision timing protocol) server which binds on interface for setting up multicasting.</p>
  
  <p>I have a following virtual interface</p>
  
  <pre><code>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
  </code></pre>
  
  <p>Now, I don't have any issues binding to a normal interface, but for any virtual interface I get a failure. </p>
  
  <pre><code> (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)
  </code></pre>
  
  <p>I need some pointers to overcome this issue. Any help here is appreciated.</p>