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HTTP SSL Certificate Expiry sensors

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I am trying to add HTTP SSL Certificate Expiry sensors to my PRTG. I have been able to add some, so I believe that my probe is configured properly, but there are a few particular ones that I'm having a problem with:

1. An Ubuntu Linux server: Is this possible with this sensor? I'm generally getting "No valid SSL certificate found" regardless of how I'm configuring the sensor.

2. Domain controllers: I'm generally getting "Unable to connect to the remote server" regardless of how I'm configuring the sensors.

3. ADFS & ADFS proxy servers: I"m generally getting "No valid SSL certificate found" regardless of how I'm configuring the sensors.

My manager tells me these servers have "certificates" but is it possible we're confusing those with what's being accomplished with this sensor in PRTG? From what I'm told, some of these servers are also using wild card certs.

linux prtg sensor

Created on May 19, 2015 3:22:14 PM



3 Replies

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Hi,

The sensor checks the SSL certificate of a server that is reachable over HTTPS.

When connecting to these servers, from your PRTG server with your internet browser (https://servername) do you get a valid response and does this include a SSL certificate?

Created on May 20, 2015 7:20:56 AM



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Sorry, for the delay in replying....

Here's my finding so far - and please excuse me if my lack of knowledge on web sites & SSL is apparent:

Server1 (Intranet site): Browsing to https://server1 results in an "unable to connect" message. However, I can browse to http://server1 and our Intranet site is displayed. Does this mean that there would be no SSL certificate? If not, isn't there some type of certificate used and does PRTG have the ability to monitor that?

Server2 (ADFS server used for Office 365): Browsing to https://server2 results in an "unable to connect" message. However, I can browse to http://server2 and an IIS default web page is displayed. Same questions as above.

Server3 - Server6 (4 domain controllers): Browsing to both https://serverx & http://serverx results in an "unable to connect" message. Same questions...

Thanks for the help, Dave

Created on May 29, 2015 7:03:10 PM



Votes:

0

Hi,

If you cannot connect to the servers using HTTPS, there is no point in setting up a sensor that checks a SSL certificate.

SSL is used to secure data traffic over HTTPS, so without HTTPS there is no SSL and no certificate.

Created on Jun 1, 2015 7:43:30 AM




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