The settings looked correct and in the events list I could see vCenter trying to send the email, DNS was fine and there were no firewall issues. Tracing on Exchange showed that the email never reached a CAS server. This meant I had to dig through the vCenter logs on the VCSA.

1. Enable the SSH (if this wasn’t done during deployment) and the Bash Shell (https://VCSA_IP:5480)






2. SSH to the VCSA and type ‘shell’ at the ‘command>’ prompt. This will open the bash shell.

3. Look at ‘messages.log’ in /var/log (‘cat /var/log/messages.log | grep sendmail’ should be sufficient)

In here I discovered something strange. My SMTP server was set to ‘’ but vCenter was trying to use just ‘’ as the relay address, therefore the connection was timing out.

2015-10-14T16:50:39.137459+00:00 VCSA1 sendmail[2803]: t9EGZCgq010289: to=<>, ctladdr=<> (0/0), delay=00:15:25, xdelay=00:00:00, mailer=esmtp, pri=210969,, dsn=4.0.0, stat=Deferred: Connection timed out with

4. At this point I logged into the vSphere Web Client and modified the SMTP address to an A record that doesn’t exist ( Back in the SSH session, I could now see entries such as below, which verified that the change took effect.

2015-10-14T16:57:38.355977+00:00 VCSA1 sendmail[30811]: t9EGU4Yx022319: to=<>, ctladdr=<> (0/0), delay=00:27:32, xdelay=00:00:00, mailer=relay, pri=300970, relay=[], dsn=5.1.2, stat=Host unknown (Name server: []: host not found)

5. Changing the SMTP server back to a valid A record ( which seemed to do the trick.

2015-10-15T12:27:32.504943+01:00 VCSA1 sendmail[28763]: t9FBRVI1028752: to=<>, ctladdr=<> (0/0), delay=00:00:01, xdelay=00:00:01, mailer=relay, pri=120873, [], dsn=2.0.0, stat=Sent (<> [InternalId=13351197] Queued mail for delivery)

While the fix at the end was pretty straight forward the troubleshooting steps are useful to know.