Hi, Having quite a few issues with mails that are getting deferred with (unknown mail transport error) Nothing has changed in main.cf or master.cf - so not sure where to check. Have done a postfix reload and postsuper -r relay=none, delay=1.6, delays=0.57/1/0/0.01, dsn=4.3.0, status=deferred (unknown mail transport error) Any advice here?
Just some more info : root@smtp-01:/etc/postfix# less /var/log/mail.log | grep -i 2EBB240E16 Aug 21 10:52:20 smtp-02 postfix/smtpd[21316]: 2EBB240E16: client=localhost[127.0.0.1] Aug 21 10:52:20 smtp-02 postfix/cleanup[22117]: 2EBB240E16: message-id=<VI1P18901MB0176EDE7E75CCE6385821F4CF7AA0@VI1P18901MB0176.EURP189.PROD.OUTLOOK.COM> Aug 21 10:52:20 smtp-02 postfix/qmgr[20247]: 2EBB240E16: from=<carol@****.co.za>, size=104257, nrcpt=1 (queue active) Aug 21 10:52:20 smtp-02 postfix/smtp[22942]: 597C241454: to=<info@****.com>, relay=127.0.0.1[127.0.0.1]:2526, delay=56, delays=56/0/0/0.64, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as 2EBB240E16)Aug 21 10:52:20 smtp-02 postfix/error[23098]: 2EBB240E16: to=<info@****.com>, relay=none, delay=0.64, delays=0.64/0/0/0, dsn=4.3.0, status=deferred (unknown mail transport error)
According to Internet Search Engines with Code: postfix "unknown mail transport error" reason could be mail aliases. If Recipient address has aliases, maybe one of them does not exist?