IBM Support

IBM AIX: sendmail Error: Deferred: Connection refused by [127.0.0.1]

Troubleshooting


Problem

  • After upgrading AIX from any level below 7200-04-01 to any level above, sendmail exhibits the following behavior even with root user:
# mail -v -s "test" user@domain < /etc/motd

user@domain... Connecting to [127.0.0.1] via relay...

user@domain... Deferred: Connection refused by [127.0.0.1]
  • Syslog also displays the following messages:
Mar 31 17:15:04 HOSTNAME mail:info sendmail[13697280]: 12VLF4CV13697280: from=root, size=1710, class=0, nrcpts=1, msgid=<202103312115.12VLF4CV13697280@HOSTNAME>, relay=root@localhost
Mar 31 17:15:04 HOSTNAME mail:info sendmail[12124634]: 12VLF4CV13697280: to=user@domain, ctladdr=root (0/0), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=121710, relay=[127.0.0.1] [127.0.0.1], dsn=4.0.0, stat=Deferred: Connection refused by [127.0.0.1]

Cause

Starting from AIX 7200-04-01, sendmail version was upgraded to 8.15.2 which works as a Mail Submission Program (MSP) rather than a Mail Transfer Agent (MTA) that worked on older versions and levels of AIX, and that requires a new configuration file named submit.cf to coexist with sendmail.cf.

Resolving The Problem

Copy /etc/mail/sendmail.cf to /etc/mail/submit.cf, as follows:
# cp -p /etc/mail/sendmail.cf /etc/mail/submit.cf
Support

If you require more assistance, use the following step-by-step instructions to contact IBM to open a case for software with an active and valid support contract.  

1.  Document (or collect screen captures of) all symptoms, errors, and messages related to your issue.

2.  Capture any logs or data relevant to the situation.

3.  Contact IBM to open a case:

   -For electronic support, see the IBM Support Community:
     https://www.ibm.com/mysupport
   -If you require telephone support, see the web page:
      https://www.ibm.com/planetwide/

4.  Provide a clear, concise description of the issue.

5.  If the system is accessible, collect a system snap, and upload all of the details and data for your case.

 - For guidance, see: Working with IBM AIX Support: Collecting snap data

Related Information

Document Location

Worldwide

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Document Information

Modified date:
27 October 2023

UID

ibm16439247