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Why are vmwaresensor and PFT sensor contacting the internet ?



My vmwaresensor and PFT sensor are attemping to contact 3 sites in on the internet every min. I hav not set this up and cannot explain it. Any ideas ? The IP addresses are, 75 and These sites resolve to addresses at akamai.com, the well known hosting service.

internet pft-sensor vmwaresensor

Created on Sep 13, 2013 1:41:38 PM

2 Replies



as both of the mentioned sensors are using the MS CryptoAPI it is not the sensors or PRTG contacting Akamai but Windows itself. This has to do with the Automatic Root Certificate Update which is implemented in the CrpytoAPI.
There is a mechanism in Windows that tries to update the local certificate store when there is a connection-attempt that returns with a certificate whose root CA is not yet stored in the local certificate store. Therefore it tries to get a file called 'authsrootstl.cab' from the akamai-cdn to get a list of all root-cas and afterwards get the new or altered ones.

It is not only the vmware-sensor that is affected by this issue but every application that uses the Microsoft CryptoAPI for getting access to ssl-secured connections.
Best regards

EDIT: See also this article!

Created on Sep 16, 2013 7:45:35 AM by  Konstantin Wolff [Paessler Support]

Last change on Sep 16, 2013 11:36:44 AM by  Konstantin Wolff [Paessler Support]



Ah ha, thanks for that! Updated the certificate store and all sorted !

Created on Sep 16, 2013 12:13:28 PM

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