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Port scan occurs periodically



Port scan occurs periodically even though the sensor is added using the procedure below

1) Adding a device

2) Checking No auto-discovery

3) Adding a ping sensor manually

4) Done

Port lists :

TCP 21, TCP 25, TCP 80, TCP 110, TCP 143, TCP 443, TCP 465, TCP 993, TCP 995, TCP 1521, TCP 3389, TCP 6200, TCP 8080, UDP 53, UDP 623

How can I prevent a port scan from occuring?

We're using PRTG Version :

auto-discovery portscan sensor

Created on Aug 4, 2020 2:29:53 AM

1 Reply



Hi there,

This sounds like the feature "recommended Sensors" which scans the target device for possible usable protocols. To disable this feature, please navigate to "Setup > System Administration > Monitoring" and check the option "Turn sensor recommendations off"

Created on Aug 4, 2020 12:14:05 PM by  Moritz Heller [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.