When SeedMode is true, the PexReactor sends a batch of addresses and calls StopPeerGracefully. It seems sometimes the peer ends up disconnecting before these messages are delivered, which makes it difficult for a new node to join the network.

It looks like we don't call .flush() in the MConnection.OnStop(). I tried adding that on the seed node, but even still the new node sometimes fails to receive any addresses from the seed.