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Exchange 2013 Round Trip




Does the SMTP/IMAP sensor actually do a full round trip as im slightly confused?

The blurb says:

"As long as your particular sensor is green (up), you know that your email server accepts emails via SMTP, that you can send emails to external destinations, that you can receive emails from external sources with your mail system, and that emails can be retrieved via POP3 or IMAP"

So ive created an outlook.com IMAP account.

PRTG on the same network as Exchange is sending an email to the on premise Exchange server that is then sending it to outlook.com. PRTG Then logs into outlook.com to check the email is there, reads it and deletes it.

Then it stops.

So its not actually checking that my Exchange server is recieving email from an external source as outlook.com is not sending an email back in?

Or am i missing something?

I thought a round trip would be out of exchange and then back into Exchange?

If this isnt the case how do you go about checking with PRTG that Exchnage is recieving email from external sources?


exchange-2013 roundtrip smtp-imap

Created on Aug 16, 2018 3:47:47 PM

3 Replies



Hi there,

Yes, PRTG simply checks if the parent device is able to send a mail from one SMTP server to another and and then retrieves the mail via its internal IMAP client. So basically:

[smtp device] -> ✉ -> [target smtp] -> ✉ -> [prtgs mail client] 

So that's basically how the round trip works. If you configure the target smtp to be the exchange as well, it will send it to itself - although I'm not entirely sure which route is taken then, i.e. if it's simply forwarded internally or if it takes any external routes. The former one would be the logical one :)

Kind regards,
Stephan Linke, Tech Support Team

Created on Aug 17, 2018 1:29:36 PM by  Stephan Linke [Paessler Support]



Yes so PRTG is going to pass its email to the Exchange server internally to int internal recieve connector and then spit it out to Outlook.com

So in my case its not a round trip as thats not actually checking if the Exchange server is recieving email frome external sources.

We had a case the other week where our exchange server for all intent and purposes looked up - but was actually under Back Pressure and was not accepting external email, but internal email was fine.

So i need to complete the round trip and actually have outlook.com send an email back to Exchange and check it go there - but i dont think this is possible?

Created on Aug 22, 2018 10:20:58 AM



Couldn't you set up two sensors, one that sends via outlook.com, the other one via your exchange and configure the other sensor vice versa? Not exactly a roundtrip all-in-one, but this way you can check that both directions are actually working properly.

Kind regards,
Stephan Linke, Tech Support Team

Created on Aug 22, 2018 11:09:27 AM by  Stephan Linke [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.