Hi all, For a couple of months, I have been having trouble receiving mail from a particular host:
Dec 14 09:24:33 mintier courieresmtpd: error,relay=::ffff:208.92.232.28,from=<apa...@clients.sevenl.net>: 417 DNS lookup failure: clients.sevenl.net. Try again later. As it happens, this host belongs to the ISP on whose network my mail server is running. It is their ticket/billing system which cannot send me any mail! I have been trying to diagnose the cause of the problem; however, it is not apparent to me what is wrong, and I have been having trouble explaining to them the situation. When I issue a lookup from my server, their DNS are returning a SERVFAIL for MX: mintier ben # cat /etc/resolv.conf nameserver 208.92.235.141 # sevenl.net's DNS nameserver 208.92.235.142 mintier ben # host -t mx clients.sevenl.net Host clients.sevenl.net not found: 2(SERVFAIL) mintier ben # host -t a clients.sevenl.net clients.sevenl.net has address 208.92.235.137 However when I do the same lookup from my office computer, I get reasonable results: Palladeon:~ ben$ host -t mx clients.sevenl.net clients.sevenl.net has no MX record Palladeon:~ ben$ host -t a clients.sevenl.net clients.sevenl.net has address 208.92.235.137 Presumably courier is rejecting messages because of the SERVFAIL. Does this demonstrate a problem with their DNS, or might I have some kind of problem on my machine? I feel I don't have a solid enough grasp of DNS (and courier's behaviour) to be sure. Thanks, -ben -- Ben Kennedy, chief magician Zygoat Creative Technical Services http://www.zygoat.ca ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ courier-users mailing list courier-users@lists.sourceforge.net Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
