david stevenson wrote:
Another problem I found on my system that produced similar slow down effects was related to having 2 network interfaces. I have an ethernet card, and a USB wireless connection, and by mistake I had got both active on the same subnet, but the ethernet was not woking due to lack of a connecting cable. It is quite impressive that packets got out at all, but each new connection took some time to start up. Hope my mistakes help someone. David
That may well have been my problem, as well. My motherboard has an onboard card which is not well supported in Linux, so I use a RealTek in a PCI slot for my cable internet connection. I'd enabled the onboard card for a test and forgotten to disable it. Once I did that, my DNS woes went away. So, the lesson is: If you aren't going to use a piece of hardware, tell your BIOS to disable it.