On 28-Dec-98 George Toft wrote:
I'v noticed several of my e-mails that I sent out on Dec 6th, have just arrived to their recipients. (Insert sarchastic remark about US Postal Service here).
How can this be? I thought there was a time-to-live associated with TCP packets, therefore, the e-mails should die? What's the scoop?
TCP "time-to-live" usually refers to the number of routers that the packet is allowed to go through ("hops") before being discarded, and has nothing to do with clock time. Regarding your delayed mail problem: what has probably happened here is that a mail forwarder has sat on them for 3 weeks (i.e. kept them spooled up without trying to forward them). It is unlikely to be failure to get a response from a downstream mailhost, since such failure usually (though not necessarily) times out after 5 days; 3 weeks would be very unusual, though not impossible. One way to check, if you can, would be to ask one of the recipients to extract the full headers from one of the delayed mails. There is usually a sequence of headers on the lines of ====================================================================== Received: from [209.0.51.4] (helo=mail.suse.com) by serenity.mcc.ac.uk with esmtp (Exim 1.92 #2) for efh@nessie.mcc.ac.uk id 0zucT5-0005Ab-00; Mon, 28 Dec 1998 13:12:19 +0000 Received: from localhost (daemon@localhost) by mail.suse.com (8.8.8/8.8.8) with SMTP id EAA16423; Mon, 28 Dec 1998 04:46:16 -0800 ====================================================================== which tells me, for instance, that a total time (Mon, 28 Dec 1998 13:12:19 +0000) - (Mon, 28 Dec 1998 04:46:16 -0800) = [GMT] (13:12:19) - (12:46:16) = 00:26:03 elapsed between receipt by mail.suse.com and receipt by the next host serenity.mcc.ac.uk; this is the sum of the time that mail.suse.com sat on it before trying to send it on to serenity.mcc.ac.uk, and the time it took to get a response from serenity and then transmit the mail. Hope this helps, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding@nessie.mcc.ac.uk> Date: 28-Dec-98 Time: 17:17:40 -------------------------------------------------------------------- - To get out of this list, please send email to majordomo@suse.com with this text in its body: unsubscribe suse-linux-e Check out the SuSE-FAQ at <A HREF="http://www.suse.com/Support/Doku/FAQ/"><A HREF="http://www.suse.com/Support/Doku/FAQ/</A">http://www.suse.com/Support/Doku/FAQ/</A</A>> and the archiv at <A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html"><A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html</A">http://www.suse.com/Mailinglists/suse-linux-e/index.html</A</A>>