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Remote SSL certificate expiry check



We manage a lot if different servers, websites and install many ssl certificates. We used to check with the HTTP SSL Certificate Expiry sensor but this is no longer possible. Is there a way / (custom) sensor with which we can check remote certificates? the new sensor is not an option because it requires to run on the host itself, which is not working for us, all we need to know is how many days till expiry.

expiry prtg ssl-certificate

Created on Dec 6, 2016 12:35:26 PM

1 Reply



Dear mccs,

Thank your for your knowledge base request.

Usually, a sensor connects to the IP Address or DNS Name of the parent device on which you created this sensor. That being said kindly note, that the SSL Certificate sensor directs its query against the parent device, not working independently of it.

Please add for every SSL Certificate a new device and create the sensor for this device. Bear in mind to set the correct IPv4 Address/DNS Name in the device settings (e.g. paessler.com). The sensor will output the days to expiration among other certificate information.

By the way, the SNI field in the sensor itself is for scenarios like one host running several virtual web servers, each with its own certificate for example.


Created on Dec 7, 2016 9:08:11 AM by  Sebastian Kniege [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.