On Thu, Sep 27, 2007 at 04:20:09PM -0700, Chris Buxton wrote: > If it were me, I would start by disabling EDNS0. This is often the > cause of problems such as this. You can try setting the buffer size > down to 512 bytes, but if that doesn't solve it, turn EDNS off entirely. > > If that solves it, then probably the forwarders are the problem. Ask > your ISP about this; they may be using some kind of security software > that is not able to handle EDNS0. Can I reliably detect whether my forwarders handle EDNS0 or not? I have tried manually querying them using host and dig (with +bufsize) and they seem to reply without a problem, but I'm not sure if that is a valid test. > There will always be some timeouts. That's just the nature of the > Internet today. But these should not result from a large percentage > of your server's resolving attempts. Thanks for reassuring me. I'm trying hard to get better service to my users -- and intermittent or random failures are particularly bothersome. -- Christian Robottom Reis | http://async.com.br/~kiko/ | [+55 16] 3376 0125 ...... ..... .... ... .. .