Comment 4 for bug 419162

For wireless networks, we definitely need the ifconfig down call. I'm not sure about wired networks. I'm always hesitant to make changes like that because something that works on my system or your system may very well break things on someone else's. Have you tried using dhclient instead of pump? That sends out more than one discover packet while trying to connect, which may give you better results. You could also try adding in time.sleep() calls to the connection code directly and see if that helps.