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Graph Last Message?

Votes:

1

Hi PRTG Support,

PRTG has provided a value (-48dBm as signal level for our wireless link), this value appears under Message column:

Screenshot

I have 2 questions in regards to this value:

  1. is it possible to graph this value?
  2. how can i set a notification if this value goes up to -70dBm?

Cheers, Richard

prtg-network-monitor regex snmp snmp-sensor string value

Created on Jun 21, 2018 6:35:52 AM

Last change on Jul 9, 2018 6:51:18 AM by  Luciano Lingnau [Paessler]



Best Answer

Accepted Answer

Votes:

1

The customer followed-up via E-mail. I will share the "solution setup" in case anyone else faces the same situation.

As pointed out by the previous reply, before being able to "evaluate" the value (from this string) one needs to extract the numerical value, for instance with a regex expression.

For this situation (A positive or negative value with one decimal place), to extract the numerical value you require the following regex expression:

(-?\d+\.\d+)

The set-up (in the sensor's settings) will look like this: Regex (Open the Image in New Tab for full-screen)

After this was configured, a new channel "Extracted Value" will come up in the sensor. When this happens, one can use the standard "limits" feature to get alert when the value goes above/below a specific threshold. This is how the limits setup would look like:

Channel Limits (Open the Image in New Tab for full-screen)

With this configuration, the sensor will go into Warning if the value goes below -55. For Notifications (as well as alerts) please add a new State Trigger for the corresponding state (Warning) to the sensor (in the Notifications tab).

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jul 9, 2018 6:45:36 AM by  Luciano Lingnau [Paessler]

Last change on Jul 9, 2018 6:51:45 AM by  Luciano Lingnau [Paessler]



4 Replies

Votes:

0

Hello there,
thank you for your inquiry.

As for #1, yes. This is possible, there are a couple of ways of doing so. Please refer to;

As for #2, as soon as the numerical value shows up in a Sensor Channel, you will be able to configure limits, alerts and everything else.

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jun 21, 2018 9:19:31 AM by  Luciano Lingnau [Paessler]



Votes:

0

Hi Luciano,

I have referred to "Can i graph text values?", but it doesn't look like we can graph it.

Will you be able to receive a screenshot if i send it to [email protected]? It will probably make more sense when you see the screenshots.

I am not sure if i can upload the screenshot on this KB.

Edit by Mod: Including screenshot shared by the user Screenshot

Created on Jun 22, 2018 2:51:43 AM

Last change on Jun 22, 2018 8:05:00 AM by  Luciano Lingnau [Paessler]



Votes:

0

Hello and thank you for your reply.

We've received your Screenshot via E-mail, I have attached it to your latest reply and inquiry. You're using the SNMP Custom String sensor. In this case, the Regular String Monitoring with Regex (described in the link) will work just fine. Please refer to the documentation/examples below:

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jun 22, 2018 8:10:58 AM by  Luciano Lingnau [Paessler]



Accepted Answer

Votes:

1

The customer followed-up via E-mail. I will share the "solution setup" in case anyone else faces the same situation.

As pointed out by the previous reply, before being able to "evaluate" the value (from this string) one needs to extract the numerical value, for instance with a regex expression.

For this situation (A positive or negative value with one decimal place), to extract the numerical value you require the following regex expression:

(-?\d+\.\d+)

The set-up (in the sensor's settings) will look like this: Regex (Open the Image in New Tab for full-screen)

After this was configured, a new channel "Extracted Value" will come up in the sensor. When this happens, one can use the standard "limits" feature to get alert when the value goes above/below a specific threshold. This is how the limits setup would look like:

Channel Limits (Open the Image in New Tab for full-screen)

With this configuration, the sensor will go into Warning if the value goes below -55. For Notifications (as well as alerts) please add a new State Trigger for the corresponding state (Warning) to the sensor (in the Notifications tab).

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jul 9, 2018 6:45:36 AM by  Luciano Lingnau [Paessler]

Last change on Jul 9, 2018 6:51:45 AM by  Luciano Lingnau [Paessler]




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