Hello,
I have setup the mail configuration in the vcenter as below:
vCenter->Configure->Settings->General:
Mail server: smtp.gmail.com:465
Mail sender: sender@gmail.com
vCenter->Configure->Advanced settings:
mail.smtp.password: PASS
mail.smtp.port: 25
mail.smtp.username: sender@gmail.com
Then I defined an alert for cpu usage above 50%. Upon triggering the alert, I see the following message in /var/mail/root
From MAILER-DAEMON@10.1.1.2 Sun Jul 5 14:44:41 2020
Return-Path: <MAILER-DAEMON@10.1.1.2>
Received: from localhost (localhost)
by 10.1.1.2 (8.15.2/8.15.2) id 065AEfdh042241;
Sun, 5 Jul 2020 14:44:41 +0430
Date: Sun, 5 Jul 2020 14:44:41 +0430
From: Mail Delivery Subsystem <MAILER-DAEMON@10.1.1.2>
Message-Id: <202007051014.065AEfdh042241@10.1.1.2>
To: postmaster@10.1.1.2
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
boundary="065AEfdh042241.1593944081/10.1.1.2"
Subject: Postmaster notify: see transcript for details
Auto-Submitted: auto-generated (postmaster-notification)
This is a MIME-encapsulated message
--065AEfdh042241.1593944081/10.1.1.2
The original message was received at Sun, 5 Jul 2020 14:44:41 +0430
from localhost
with id 065AEfdg042241
----- The following addresses had permanent fatal errors -----
<sender@gmail.com>
(reason: 530-5.7.0 Authentication Required. Learn more at)
----- Transcript of session follows -----
... while talking to smtp.gmail.com.:
>>> MAIL From:<> SIZE=2033
<<< 530-5.7.0 Authentication Required. Learn more at
<<< 530 5.7.0 https://support.google.com/mail/?p=WantAuthError a123sm10700081wmd.28 - gsmtp
554 5.0.0 Service unavailable
--065AEfdh042241.1593944081/10.1.1.2
Content-Type: message/delivery-status
Reporting-MTA: dns; 10.1.1.2
Received-From-MTA: DNS; localhost.localdomain
Arrival-Date: Sun, 5 Jul 2020 14:44:41 +0430
Final-Recipient: RFC822; sender@gmail.com
Action: failed
Status: 5.7.0
Diagnostic-Code: SMTP; 530-5.7.0 Authentication Required. Learn more at
Last-Attempt-Date: Sun, 5 Jul 2020 14:44:41 +0430
--065AEfdh042241.1593944081/10.1.1.2
Content-Type: message/rfc822
Return-Path: <MAILER-DAEMON>
Received: from localhost (localhost)
by 10.1.1.2 (8.15.2/8.15.2) id 065AEfdg042241;
Sun, 5 Jul 2020 14:44:41 +0430
Date: Sun, 5 Jul 2020 14:44:41 +0430
From: Mail Delivery Subsystem <MAILER-DAEMON>
Message-Id: <202007051014.065AEfdg042241@10.1.1.2>
To: <sender@gmail.com>
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
boundary="065AEfdg042241.1593944081/10.1.1.2"
Subject: Returned mail: see transcript for details
Auto-Submitted: auto-generated (failure)
This is a MIME-encapsulated message
--065AEfdg042241.1593944081/10.1.1.2
The original message was received at Sun, 5 Jul 2020 14:44:40 +0430
from localhost.localdomain [127.0.0.1]
----- The following addresses had permanent fatal errors -----
<receiver@gmail.com>
(reason: 530-5.7.0 Authentication Required. Learn more at)
----- Transcript of session follows -----
... while talking to smtp.gmail.com.:
>>> MAIL From:<sender@gmail.com> SIZE=1009 AUTH=<>
<<< 530-5.7.0 Authentication Required. Learn more at
<<< 530 5.7.0 https://support.google.com/mail/?p=WantAuthError a123sm10700081wmd.28 - gsmtp
554 5.0.0 Service unavailable
--065AEfdg042241.1593944081/10.1.1.2
Content-Type: message/delivery-status
Reporting-MTA: dns; 10.1.1.2
Received-From-MTA: DNS; localhost.localdomain
Arrival-Date: Sun, 5 Jul 2020 14:44:40 +0430
Final-Recipient: RFC822; receiver@gmail.com
Action: failed
Status: 5.7.0
Diagnostic-Code: SMTP; 530-5.7.0 Authentication Required. Learn more at
Last-Attempt-Date: Sun, 5 Jul 2020 14:44:41 +0430
--065AEfdg042241.1593944081/10.1.1.2
Content-Type: message/rfc822
Return-Path: <sender@gmail.com>
Received: from 10.1.1.2 (localhost.localdomain [127.0.0.1])
by 10.1.1.2 (8.15.2/8.15.2) with ESMTPS id 065AEedh042239
(version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NO)
for <receiver@gmail.com>; Sun, 5 Jul 2020 14:44:40 +0430
Received: (from root@localhost)
by 10.1.1.2 (8.15.2/8.15.2/Submit) id 065AEexC042238;
Sun, 5 Jul 2020 14:44:40 +0430
Date: Sun, 5 Jul 2020 14:44:40 +0430
Message-Id: <202007051014.065AEexC042238@10.1.1.2>
To: receiver@gmail.com
From: sender@gmail.com
Subject: =?utf-8?B?QWxhcm0gdGVzdF9jcHUgb24gSG9zdCA6IDEwLjEuMS4xMDIgaXMgWWVsbG93?=
Content-type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
VGFyZ2V0OiAxMC4xLjEuMTAyIApQcmV2aW91cyBTdGF0dXM6IEdyZWVuIApOZXcgU3RhdHVzOiBZZWxsb3cgCiAKQWxhcm0gRGVmaW5pdGlvbjogCihbWWVsbG93IG1ldHJpYyBJcyBhYm92ZSA1MCVdKSAKIApDdXJyZW50IHZhbHVlcyBmb3IgbWV0cmljL3N0YXRlOiAKIE1ldHJpYyBDUFUgVXNhZ2UgPSA1MiUgCiAKRGVzY3JpcHRpb246IApBbGFybSAndGVzdF9jcHUnIG9uIDEwLjEuMS4xMDIgY2hhbmdlZCBmcm9tIEdyZWVuIHRvIFllbGxvdw==
--065AEfdg042241.1593944081/10.1.1.2--
--065AEfdh042241.1593944081/10.1.1.2--
So, why it fails with authentication error?
