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

Alert on 30% traffic increase




is it possible to configure an alert (Notification) if the measured value of a sensor increases by x percent within a configurable window of minutes/hours?

Example: I'm monitoring the router interface to the internet.

I want to be able to configure a notification if the reported bandwidth/throughput on that interface 'sharply' increases (traffic spike) for 50% within a window of 10 minutes. Similar to the threshold notification, just not based on a fixed value (bandwidth), but on an increase by x percent.

BTW: I know the automatic monitoring (and alerting) of the measured values (comparing the current value with the value of the same period last week), but that's not what I want.



alert notification percentage

Created on Aug 4, 2014 1:44:24 PM

6 Replies



Dear Kurt

Notifications can only be triggered by absolute values, not by "increase of X% over Y amount of time".

If you absolutely need this function and if CPU utilization is no issue, you could write a script which is run as sensor using the "Exe/Script sensor". That script could query historic data using the PRTG API and compute the derivation to return a value on which you set a limit in the channel configuration to trigger a notification.

The PRTG API documentation is integrated into the PRTG interface, menu Setup / PRTG API. The tab "HTTP API" describes how to pass the login credentials, the tab "Historic Data" shows how to query historic data as either CSV or XML.

Please note that PRTG allows only up to five historic data API requests per second to keep the CPU and I/O load at a reasonable level.

Created on Aug 5, 2014 9:05:30 AM by  Arne Seifert [Paessler Support]



Yes, I thought of the script solution myself, but wanted to check if there is a 'hidden' feature I might have missed....

Would that be a feature you are interested to add?

>Please note that PRTG allows only up to five historic data API requests per second to keep the CPU and I/O load at a reasonable level.

Is that a limit per client IP or per PRTG core server? What kind of response would I get if I hit that limit?

BTW: Is there a limit for the amount of historic data I can fetch in one API call?

Created on Aug 5, 2014 10:19:28 AM



Dear Kurt

If the core gets more API queries for historic data, the new one will be put in a queue and processed later.

An API call can span the entire history of a sensor, but it can take some time to complete this request.

About the feature request: We collect all feedback from our users to determine the direction in which we develop PRTG further. Because we think of PRTG as standard software, not every request can be implemented. The PRTG API fills the role to allow further customisation by the user.

If we see high demand for a feature, it will be placed higher on our internal wish-list: https://www.paessler.com/blog/2012/07/03/other/how-we-rate-your-feature-requests-company-culture-2

Created on Aug 5, 2014 4:01:36 PM by  Arne Seifert [Paessler Support]



Dear Arne,

while the 'bang_for_buck' method is a viable approach, it has one drawback: Customers don't know if a feature they have suggested will ever be implemented and if not, why not. That's frustrating and annoying from a customers perspective. Same for my feature request above. You did not answer my question if you would be interested to implement it ;-))

Thus, I'd like to suggest a second method for feature requests, as I have seen that with other vendors and it looks like they are pretty successful with that tool.

You could use a system like Uservoice (https://www.uservoice.com/) to get direct feedback from the customers. I know that system especially from Astaro (now Sophos). Example: http://feature.astaro.com/forums/17359-utm-formerly-asg-feature-requests/filters/top

With such a system you could get a direct feedback from the customers. Those who are using the system can vote for a feature if they think it would make the product better. You as a vendor can still decline a feature and explain why it won't be implemented (Annoyance Factor, Boah effect, Developer Days, etc.). The whole process of feature requests would be much more transparent for your customers and that's what people like a lot these days.

Just a thought...

Regards Kurt

Created on Aug 6, 2014 8:28:25 AM



Dear Kurt

In software development, a feature can take much longer to implement than expected. We rather don't make promises. We are still interested in feedback. The best way is to contact us by [email protected]

From time to time, we send emails to our users, asking for feedback. Another source is the feedback of our partners.

As we try to keep the user interface of PRTG as clean as possible, we only implement a feature of which we are sure is useful for a lot of users. We have currently no plans to implement a notification trigger which fires when an X amount of increase/decrease happened over Y time.

Created on Aug 6, 2014 9:14:12 AM by  Arne Seifert [Paessler Support]

Last change on Aug 6, 2014 9:14:38 AM by  Arne Seifert [Paessler Support]



Hello Kurt

You could trigger a notification on "Unusual", but as we speak of suggestions ... i miss custom values for "Unusual".

The default is <20% of average or >500% of average per hour and per 24h.
Settings found under Setup -> System Administration -> Monitoring

Jens Tore Fremmegaard, ServerParkering AS
Paessler Certified Monitoring Professional

Created on Aug 13, 2014 7:19:33 AM

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.