Date: Wed, 24 Apr 2002 12:08:48 -0500 From: "Kevin Kinsey, DaleCo, S.P." <kdk@daleco.biz> To: "Jan Grant" <Jan.Grant@bristol.ac.uk> Cc: <questions@FreeBSD.ORG> Subject: Re: DNS port Number, Protocol Message-ID: <004201c1ebb2$b407ca40$b9e2910c@daleco> References: <Pine.GSO.4.44.0204241422250.23534-100000@mail.ilrt.bris.ac.uk>
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Thanks, I'll look into it, but everybody except AT&T says my DNS is "jolly good". (Pardon the dumb Yank for throwing that at 'ya.) The specific problem is that "email" from my cellphone to daleco.biz returns undeliverable, immediately. The latest theory is that AT&T wireless does a ping to determine whether or not a domain exists, and since I've got that blocked, they write me off their own lists......"never a dull moment," I guess. Thanks for the assist..... Kevin Kinsey, DaleCo, S.P. From: "Jan Grant" <Jan.Grant@bristol.ac.uk> To: "Benjamin Krueger" <benjamin@macguire.net> Cc: "Kevin Kinsey, DaleCo, S.P." <kdk@daleco.biz>; "freebsd-questions" <freebsd-questions@freebsd.org> Sent: Wednesday, April 24, 2002 8:24 AM Subject: Re: DNS port Number, Protocol > On Tue, 23 Apr 2002, Benjamin Krueger wrote: > > > * Kevin Kinsey, DaleCo, S.P. (kdk@daleco.biz) [020423 21:36]: > > > > From: "Benjamin Krueger" <benjamin@macguire.net> > > > > * Kevin Kinsey, DaleCo, S.P. (kdk@daleco.biz) [020422 16:07]: > > > > > I've been having some DNS troubles > > > > > with AT&T wireless (!) and my server. > > > > > > > > > > Everyone says my DNS is fine (except > > > > > AT&T). Some lightning bolt just hit me and > > > > > I decided to check if upd/53 was open > > > > > from outside....it isn't. > > > > > > > > > > What's the chance that whatever they're > > > > > using wants upd/53 instead of tcp/53? > > > > > > > > > > Kevin Kinsey > > > > > > > > Well, considering DNS uses udp 53, and only falls back on tcp 53 for overly large transfers I'd say the chances are pretty good. =) > > > > > > > > Can you describe the actual problem you're having? > > > > > > > > -- > > > > Benjamin Krueger > > > > > > > New thought is that blocked ICMP echo request > > > does not allow their server to utilize UDP port > > > #53 for DNS.....sound likely? > > > > > > Kevin Kinsey > > > > While blocking ICMP is not always the most clever of ideas, it shouldn't > > prevent UDP from working. Your best bet here is to pull out your trusty packet > > sniffer and watch to see if the dns server is recieving any of the packets. > > I don't know if this has already been covered, but if you've opened up > port 53 (UDP _and_ TCP) and you want your named to be able to resolve, > as well as answer queries, then you need to ensure it's sending its own > queries on port 53. By default, I think it still uses transient port > numbers (which, on recent stable, have moved up into the high port > range). > > -- > jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/ > Tel +44(0)117 9287088 Fax +44 (0)117 9287112 RFC822 jan.grant@bris.ac.uk > Semantic rules, OK? To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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