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How to make Custom OID with no value to be false positive



Our equipment will not give any value on the custom OID if the port is alarm free and only give string value if only got alarm on it per example below: = "Loss of Signal" [ASN_OCTET_STR] = "Loss of Signal" [ASN_OCTET_STR]

is there any way that i can make the custom OID with no value to be false positive and change the state to UP, and when there's value it will change it state to Down.

sensor snmp snmp-sensor

Created on Feb 8, 2019 2:22:38 AM

1 Reply



Dear Afiq,

an OID with actually no value cannot be processed in PRTG. Getting no value will result in a sensor error status.

You can use the SNMP Custom String Lookup sensor to translate a string to a value, and back, using a custom-made lookup file.

This means, only the other way is possible, if the OID yields no value, the sensor is going down. You can then create a Factory sensor in order to invert the status with a custom status formula. Please scroll down to chapter "Define Sensor Status—status() Function" to see how it is done.

Created on Feb 8, 2019 12:06:12 PM by  Arne Seifert [Paessler Support]

Last change on Feb 8, 2019 12:06:36 PM by  Arne Seifert [Paessler Support]

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