GetMyExternalIP() is currently breaking. #3058

Due to showmyip.com being down, GetMyExternalIP() currently fails in some cases. There's not much excuse for this, as there's hundreds of similar sites that could be used instead. There's a contingency plan in the file below that should probably be enacted, if nothing else.

https://github.com/bitcoin/bitcoin/blob/e0d6dd11e3d9246b510a78118497d81b6d94ee14/src/net.cpp#L357

No, there is not much excuse for using a centeralized service. We should have stopped using this a long time ago. The bitcoin network itself already provides the required service. ... it's also not that urgent anymore, since UPNP provides it in cases where the host is behind nat and gets the address via UPNP and the externalip argument provides it in cases where users have manually configured it.

I posted a for-comment patch a while back: http://people.xiph.org/~greg/extip.patch

But I need to do more testing of it before I can propose merging it.

I rememeber I have an open issue somehow related to this and perhaps we can just find a way to remove the use of these kind of services... I think it's time :). It was #2280.

See #3088 for the solution. Closing this one, as it can be considered a duplicate of #2280.