[CentOS] Fail2ban mail failures ???

[Mike Burger]

On 2014-12-26 12:39 pm, Robert G. (Doc) Savage wrote:
> I'm using fail2ban with CentOS 6.6. Something is causing fail2ban's
> alerts sent to root's mail to be rejected. Here's a clip from one of 
> the
> error messages:
> 
> 
>         Message 48:
>         From MAILER-DAEMON at lion.protogeek.org  Sun Dec 21 03:09:20 2014
>         Return-Path: <MAILER-DAEMON at lion.protogeek.org>
>         Date: Sun, 21 Dec 2014 03:09:19 -0600
>         From: Mail Delivery Subsystem 
> <MAILER-DAEMON at lion.protogeek.org>
>         To: postmaster at lion.protogeek.org
>         Content-Type: multipart/report; report-type=delivery-status;
>         	boundary="sBL97EKS003880.1419152959/lion.protogeek.org"
>         Subject: Postmaster notify: see transcript for details
>         Auto-Submitted: auto-generated (postmaster-notification)
>         Status: R
> 
>         Part 1:
> 
>         The original message was received at Tue, 16 Dec 2014 03:09:17
>         -0600
>         from localhost
>         with id sBG97E83025627
> 
>            ----- The following addresses had permanent fatal errors
>         -----
>         <fail2ban at example.com>
> 
>            ----- Transcript of session follows -----
>         <fail2ban at example.com>... Deferred: Connection timed out with
>         example.com.
>         Message could not be delivered for 5 days
>         Message will be deleted from queue
>         ..........
> 
> 
> 
> I used to get the messages that are now being deleted after five days.
> Any suggestions?

I would suggest looking at the mailer daemon logs on both the sending 
and receiving systems. It would appear that the sending system is having 
difficulties at the receiving system end.

You will likely find the root of your issues in the log entries for that 
message (or those messages) that occurred over the 5 days in question.

-- 
Mike Burger
http://www.bubbanfriends.org

"It's always suicide-mission this, save-the-planet that. No one ever 
just stops by to say 'hi' anymore." --Colonel Jack O'Neill, SG1