Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!ames!mailrus!tut.cis.ohio-state.edu!triceratops.cis.ohio-state.edu!karl From: karl@triceratops.cis.ohio-state.edu (Karl Kleinpaste) Newsgroups: comp.mail.sendmail Subject: Re: Unknown Host Error Message-ID: <19567@tut.cis.ohio-state.edu> Date: 9 Aug 88 14:07:41 GMT References: <277@hal.UUCP> <5951@orstcs.CS.ORST.EDU> Sender: news@tut.cis.ohio-state.edu Lines: 20 In-reply-to: hakanson@mist.cs.orst.edu's message of 9 Aug 88 00:15:26 GMT hakanson@mist.cs.orst.edu writes: >I do not understand how named and sendmail can resolve the name AND the >host still be UNKNOWN! This rather surprising behavior can occur when (for example) someone has an MX record pointing to an unknown host. It can also happen if there is inconsistent data among a domain's various nameservers out there. In the last several months, I have caught 3 or 4 instances where mail to some.site.domain got bounced with `host unknown,' but when I later made a fast check for the host, I got valid A or MX records. On checking ALL of the nameservers for the given host, 2 out of 3 had the correct data, the 3rd gave me an authoritative denial of existence. Oops. Can you guess on which nameserver my machine managed to have a grip when that mail was trying to go through? I generally try to duplicate the inconsistency in a typescript that I can then send to the person identified in the SOA record. --Karl