What is this?

This knowledgebase contains questions and answers about PRTG Network Monitor and network monitoring in general.

Learn more

PRTG Network Monitor

Intuitive to Use. Easy to manage.
More than 500,000 users rely on Paessler PRTG every day. Find out how you can reduce cost, increase QoS and ease planning, as well.

Free Download

Top Tags

View all Tags

Port Scanning Sensor - Support More than 42 Ports Scannable in 15 Minute Timeout



Want this feature implemented, too? Please upvote by clicking Thumbs up!

(Posts as a reply won't be published in this feature request thread. Read Me!)

User Story

As a PRTG User, I want to be able to use the Port Scanner sensor to scan more than 42 ports.

Details of User Story

The port scanning sensor in PRTG is great in theory - scan a range of ports and detect how many are Up or Down. We wanted to be able to scan common ports 1-1023 from probes in banned geographies to ensure zero ports are open. We also wanted to be able to use this as a manner of change detection inside our service area, so if the range for a given host should have 1 port open and suddenly 5 are open, we'd like to know.

Unfortunately, hard-coded into PRTG according to support, is that this sensor will only support a maximum of 42 ports to scan.

Specifically, this is the answer received:

""Port-by-Port Delay" setting sets the time between two connection tries and therefore does not help here, it should be 0. The customer should be able scan 42 Ports per sensor. (900/21= 42) ​ This timing is set in the code and not able to be changed. I've confirmed their numbers here. If I go over 42, the sensor times out. ​ Also, there isn't any way to test with this, as the function is built into the code base for PRTG. I'm sorry we can't meet your needs when it comes to this."

The feature request is to make whatever adjustments are required to support more ports scanned on this sensor. The customer alternative right now would be to make dozens of sensors which, when replicated across hundreds of IPs, creates an enormous number of sensors to maintain.

Acceptance criteria

  • Port scanner sensor can scan at least 1024 ports per sensor, preferably more, in the maximum 900 second timeout



improve-prtg port-scanner prtg-kbtracker

Created on Nov 4, 2020 2:44:59 PM


Nobody has replied yet

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.