"Domain of sender address does not exist" or "DSN: Data format error"

Products

• VMware vCenter Server

Issue/Introduction

vCenter Alarms like "Domain of sender address does not exist" or "DSN: Data format error"  are triggered when email sender Domain is unresolved.

• The E-Mails sent by the vCenter Server Appliance will be rejected by the customer's mail server.
• In /var/log/messages.log, you see entries similar to:

2017-10-23T10:48:59.567720+02:00 vcenter sendmail[55361]: hostname: hostname: DSN: Data format error
2017-10-23T10:48:59.592809+02:00 vcenter sendmail[55362]: hostname: from=<[email protected]>, size=429, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=photon-machine [127.0.0.1]
2017-10-23T10:48:59.607661+02:00 vcenter sendmail[55362]: hostname: from=<>, size=2421, class=0, nrcpts=1, msgid=<[email protected]>, proto=ESMTP, daemon=MTA, relay=photon-machine [127.0.0.1]
2017-10-23T10:48:59.644144+02:00 vcenter sendmail[55361]: hostname: [email protected], delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=31453, relay=[127.0.0.1], dsn=2.0.0, stat=Sent (hostname Message accepted for delivery)
2017-10-23T10:49:03.964029+02:00 vcenter sendmail[55364]: hostname: to=<[email protected]>, delay=00:00:04, xdelay=00:00:04, mailer=relay, pri=122421, relay=mail.example.com [192.0.2.123], dsn=2.0.0, stat=Sent (Ok: queued as A5EA0B40C3)  

Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

Environment

VMware vCenter Server Appliance 6.5.x
VMware vCenter Server Appliance 6.7.x

Cause

This issue occurs when vCenter Server Appliance is not able to lookup the DNS record for the sender Email address Domain.

Resolution

This issue is resolved in:

• vCenter Server Appliance 6.5 Update 2
• vCenter Server Appliance 6.7 Update 1

 

Workaround:
To work around this issue if you do not want to upgrade,

• Edit the /etc/hosts file of vCenter Server Appliance and add the following line:

192.0.2.123 example.com

Where 192.0.2.123 is the IP of the mai lserver and example.com is the domain used to send the email from.