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When adding additional SSL Certificate Sensors to a server the previous SSL sensors change to match



When adding additional SSL Certificate Sensors to a server the previous SSL sensors change to match the newest sensor settings including Common Name and Thumbprint associated with sensor.

I have multiple certificates on the same server. They are bound to port 443 on different IP addresses. Each time I manually add a SSL sensor I put in its name and use the default setting otherwise. As soon as I save it ALL of my other SSL sensors that were previously a different setting immediately change to match the new sensor's settings. Sorry to be repetitive. I am sure that this is something simple but so far I have had no luck finding out what I am doing wrong. By the way all of the sensors work for each time I set them up, they all greened up, they just change like lemmings every time I add a new one.

duplicate sensor ssl

Created on Oct 31, 2018 7:29:18 PM

2 Replies

Accepted Answer



Hello there,
thank you for your KB-Post.

Are these internal hosts/certificates, or something that is publicly accessible? (This would allow us to reproduce the setup here)

Or, are you able to share a couple of screenshots illustrating the setup and outcome?

You might also want to refer to this:

Please keep in mind that there should be one device (with one sensor) per FQDN that you want to monitor. If you had multiple certificates on the same port on the same host, you could use SNI to query specific certificates. Or, if you were using different ports for each certificate, a different port in each sensor.

But with different IP's, you would actually need different devices in PRTG (one for each available Address). The reason being, if each certificate is only available on one IP, your DNS server is probably doing a Round-Robin and whenever the response is IP A, all sensors will end up querying certificate A. And when the DNS responds with IP B, all sensors end up polling the certificate used on IP B.

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Nov 1, 2018 1:03:19 PM by  Luciano Lingnau [Paessler]



Luciano, Sorry for the late reply. Thanks for your help on this. I did indeed have multiple certificates on my server. I created individual devices for each sensor with the IP setting that was bound for the specific website. Then I created a SSL certificate sensor under the each device and they worked perfectly!

Thanks Again! Jarrett

Created on Feb 6, 2019 1:58:59 PM

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