controller cannot see minimServer

[simoncn]

(16-08-2012 09:42)psme Wrote:  A quick search on ohNet gives:

https://github.com/openhome/ohNet/blob/master/Os/Os.h

With a function call like:
int32_t OsNetworkBindMulticast(THandle aHandle, TIpAddress aAdapter, TIpAddress aMulticast, uint32_t aPort);

It seems ohNet does handle some multicast binding operation. If for some reason such function fail, then ohNet may not receive any multicast message, hence causing the problem.

Or I have no idea what I'm talking about!

This ohNet code is binding to a multicast socket, not subscribing to a multicast group. Subscribing is a lower-level IGMP protocol that is implemented by the OS networking stack. If this bind call were to fail, MinimServer would never be able to receive any multicast messages, not even when it's first started.

The IGMP subscription should be maintained by the OS networking stack as long as the multicast socket is bound by the ohNet library in the MinimServer process. On Windows, you can check this by issuing the netstat -a -o command. In the output, you'll see a section like this:

Code:

UDP    192.168.0.14:123       *:*                                    2292
UDP    192.168.0.14:427       *:*                                    3996
UDP    192.168.0.14:1030      *:*                                    2508
UDP    192.168.0.14:1900      *:*                                    16932
UDP    192.168.0.14:1900      *:*                                    2508
UDP    192.168.0.14:1900      *:*                                    2508
UDP    192.168.0.14:5353      *:*                                    1892

The number on the right is the process ID of the owning process (16932 for MinimServer). If the bind call has failed, this entry won't be present.

Quote:Anyway, hope this problem happen again so I can do some network sniffing...

I think you'll find that the IGMP queries for the SSDP multicast group are no longer being received by the device (PC or QNAP). If the multicast listening socket 1900 is still bound by the MinimServer process and the IGMP queries aren't being received, this would be conclusive evidence of a network problem.