From owner-freebsd-hackers Tue Nov 19 18:59:20 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id SAA27992 for hackers-outgoing; Tue, 19 Nov 1996 18:59:20 -0800 (PST) Received: from scanner.worldgate.com (scanner.worldgate.com [198.161.84.3]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id SAA27985 for ; Tue, 19 Nov 1996 18:59:18 -0800 (PST) Received: from znep.com (uucp@localhost) by scanner.worldgate.com (8.7.5/8.7.3) with UUCP id TAA06625; Tue, 19 Nov 1996 19:58:47 -0700 (MST) Received: from localhost (marcs@localhost) by alive.ampr.ab.ca (8.7.5/8.7.3) with SMTP id TAA07385; Tue, 19 Nov 1996 19:58:09 -0700 (MST) Date: Tue, 19 Nov 1996 19:58:09 -0700 (MST) From: Marc Slemko X-Sender: marcs@alive.ampr.ab.ca Reply-To: Marc Slemko To: Joerg Wunsch cc: FreeBSD hackers Subject: Re: sendmail without DNS (was: Re: BoS: Exploit for sendmail smtpd bug (ver. 8.7-8.8.2).) In-Reply-To: <199611190042.BAA03594@uriah.heep.sax.de> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk On Tue, 19 Nov 1996, J Wunsch wrote: > As Marc Slemko wrote: > > > I have tried nocanonify, nodns, a service.switch file and perhaps a few > > other things that I can't remember right now, but sendmail still tries to > > do DNS lookups. > > You must do something wrong. I'm using a local nameserver, but as you > can see, it's only used for local lookups: ...and if you are setup to use a remote nameserver then it will try to use that. Therefore, you aren't disabling lookups. A local nameserver can work around the problem though. [...] > > uriah # kill -STOP `cat /var/run/named.pid ` > uriah # (echo "/bind/s/^/#"; echo "w"; echo "q") | ed /etc/host.conf > 105 > #bind > 106 Aha. This is a way of working around it that I had temporarily forgot about. With hosts before bind in /etc/host.conf, and an entry for the local hostname in /etc/hosts, the lookup will be avoided. I forgot about that because there is some reason (can't remember it right now; could be something that was fixed long ago) why I couldn't do that to host.conf on the particular machine because it interfered with something else. However, in the general case for someone getting mail via uucp with a dial on demand type network connection that will solve the problem. Thanks. > uriah # echo "hi you" | mail -s "test mail" marcs@znep.com > uriah # mailq > Mail Queue (1 request) > --Q-ID-- --Size-- -----Q-Time----- ------------Sender/Recipient------------ > BAA03279* (no control file) > > (Well, that's the queue file from my /etc/daily that's just running > right now. Your mail did already go out to the UUCP spool by that > time, no additional delay for nameserver attempts etc.) If you don't have your machine setup so that it thinks it can reach a nameserver outside and there is a route to that nameserver, you won't notice any extra delays.