vCenter Server Email alerts fail to deliver due to outdated SMTP Credentials

Products

• VMware vCenter Server

Issue/Introduction

• Alarms and events trigger correctly within the vSphere Client UI.

• Email notifications are not received by administrators.

• The sendmail logs present in /var/log/messages file on the vCenter server contain the following error: 

  YYYY-MM-DDTHH:MM:SS vcenter sendmail[####]: ###########: to=<smtp_email>, delay=<time>, xdelay=00:00:12, mailer=relay, pri=1202421, relay=<smtp_server> [<smtp_server_IP>], dsn=5.7.57, reply=530 5.7.57 Client not authenticated to send mail. Error: 535 5.7.139 Authentication unsuccessful, the user cred...s were incorrect. [<smtp_email> <time_stamp> ###########], stat=Service unavailable
YYYY-MM-DDTHH:MM:SS vcenter sendmail[####]: ###########: ###########: return to sender: Service unavailable
...

  YYYY-MM-DDTHH:MM:SS vcenter sendmail[####]: ###########: to=<smtp_email>, delay=<time>, xdelay=00:00:00, mailer=relay, pri=1292421, relay=<smtp_server>, dsn=4.4.2, stat=Deferred: Connection reset by <smtp_server>

Environment

vCenter Server 8.x

 

Cause

The vCenter Server is configured with an outdated SMTP account password. This occurs when the password for the email account used for relay is changed at the source but not synchronized within the vCenter Server's Mail configuration.

Resolution

To restore email functionality, manually update the SMTP password in the vCenter Server settings:

1. Log in to the vSphere Client and select the vCenter Server object in the inventory.
2. Go to Configure > Settings > Advanced Settings.
3. Click Edit Settings, locate the parameter mail.smtp.passwordand update the value with the correct, current password for the SMTP account.
4. Click Save to apply the changes.
5. Manually trigger a test alarm to verify that email notifications are now successfully delivered.

Additional Information

Setting Up Email Notifications for Alarms generated in vCenter Server (KB 376894)