Nagios Support Forum

Do you see any errors in your SMTP server when the SMS message is not sent?

None. Message tracing shows the message received by our on-premises Exchange server, the handoff from local to remote Exchange, and remote mail server shows it as delivered. No received at the contact address and no NDR as yet received.

If you see the message leave the Nagios server and it was received by the exchange server (the SMTP server in XI) then it is being blocked somewhere else and not an issue with the Nagios server.

I came to the same conclusion. We are effectively stuck as without an NDR we cannot determine the reason the message was not delivered. As it stands we can go ahead and lock this thread. The means has been provided to have Nagios send the notifications. Our only option now is to try to work out with the recipient provider a reason for non-delivery.

My thanks to everyone who helped out on this one.

If you have access to the email address in the from field in the Manage Email Settings screen, there may be an error or reason it was not deliveredsent to that account.

I was getting rare successes in addition to the failures without any change to the address so the address on the contact is correct.

OK, thanks for the information. I'll close and lock this post, but if you have any new questions, please feel free to open a new post.