[coherence-dev] Send discovery response delayed

[Caleb Callaway]

Hi all,

I’m evaluating Coherence for use as a discovery service on a networked
vision system for industrial automation. I’ve gotten Coherence working in my
testbed environment (Debian 3.1—Sarge), and the test discovery seems to
work, but it’s inconsistent. Oftentimes when I start the program for the
first time, I get something along these lines:

INFO  ssdp                        Feb 23 14:58:36  send discovery response
delayed by 0s for uuid:20a01035-2f25-43c2-9f76-1e494024c619::upnp:rootdevice
to ('192.168.1.102', 57316) (coherence/upnp/core/ssdp.py:172)
INFO  ssdp                        Feb 23 14:58:36  send discovery response
delayed by 0s for
uuid:20a01035-2f25-43c2-9f76-1e494024c619::urn:schemas-upnp-org:device:Media
Server:2 to ('192.168.1.102', 57316) (coherence/upnp/core/ssdp.py:172)
INFO  ssdp                        Feb 23 14:58:36  send discovery response
delayed by 0s for uuid:20a01035-2f25-43c2-9f76-1e494024c619 to
('192.168.1.102', 57316) (coherence/upnp/core/ssdp.py:172)
INFO  ssdp                        Feb 23 14:58:39  send discovery response
delayed by 3s for
uuid:20a01035-2f25-43c2-9f76-1e494024c619::urn:microsoft.com:service:X_MS_Me
diaReceiverRegistrar:1 to ('192.168.1.102', 57316)
(coherence/upnp/core/ssdp.py:172)
INFO  ssdp                        Feb 23 14:58:39  send discovery response
delayed by 3s for
uuid:20a01035-2f25-43c2-9f76-1e494024c619::urn:schemas-upnp-org:service:Cont
entDirectory:2 to ('192.168.1.102', 57316) (coherence/upnp/core/ssdp.py:172)
INFO  ssdp                        Feb 23 14:58:39  send discovery response
delayed by 3s for
uuid:20a01035-2f25-43c2-9f76-1e494024c619::urn:schemas-upnp-org:service:Conn
ectionManager:2 to ('192.168.1.102', 57316)
(coherence/upnp/core/ssdp.py:172)

192.168.1.102 is the IP address of the computer I’m using to browse
available UPnP devices. The complete log is attached. 

When I see these messages, it delays the discovery of the Coherence service,
sometimes for minutes at a time. Occasionally, discovery never occurs until
I restart Coherence. Does anyone have any idea why that might be? I suspect
it has to do with the underlying routing mechanisms in Linux, but I don’t
know exactly how or what.

Any advice would be appreciated. The full log is available here:
http://pastebin.com/m32eeb194

Thanks,
-Caleb