The title of this thread is not completely correct.
I have two N+s on my network:
1) Netduino+ "A" is sending http request to "B" upon a button press (uses Socket.Connect())
2) Netduino+ "B" is listening for http requests (uses Socket.Listen())
While Running 4.1:
I have confirmed mattcro's experience, except I find that the network cable may be unplugged during boot, as long as Socket.Connect() is not called. If I unplug "B" so that the Socket.Connect() fails, an exception is thrown (which is caught) and "A" recovers as expected. The failure is specific to calling Socket.Connect() while the ethernet cable is unplugged.mattcro: If Netduino has an internet connection at boot, but the internet connection is lost after boot (ie router-switch cable unplugged while application is running), then the next connection attempt does not succeed (obviously) but neither does it time out. It gets stuck at socket.Connect(). The Netduino does not seem to be locked up completely, because my app has a timer event driven LED blink that keeps working.
"B" can have the network unplugged at ANY time and recovers well when the network is restored.
With Running 4.2 RC4 on "A":
If "A" is booted without the Ethernet cable, the network port does not work. This is different from 4.1.
If "A" is allowed to boot with the Ethernet cable, the ethernet cable may be pulled at any other time, consistent with mattcro's experience.
I must go to bed, otherwise I would try 4.2 RC4 on "B", I suspect that booting without Ethernet will cause the ethernet port to not work. Maybe I can test this tomorrow.
There is another unrelated network issue with busy networks causing the network port to shut down. I have found this to be true with 4.1 and 4.2.
A similarity with the Socket.Connect() problem is that when the busy network shutdown happens, internally the N+ is unaware. Even "pings" to the "localhost" are returned, while externally... nothing. I have one fairly busy network that causes the N+ network to die withing minutes, and then I have a very quiet network and have had a pair of N+'s running for days.
Sure would be great if there were a fix for both these problems.
Wish I knew enough to help with fixing the problem, maybe someday I will be more skilled.
-kluger