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SNMP Custom by using OID no working



I using Paessler snmp tester, i can get the result (refer the snmp walk below) = "0" [ASN_UNSIGNED] = "29" [ASN_UNSIGNED] = "108" [ASN_UNSIGNED] = "0" [ASN_UNSIGNED]

when i using same OID listed above. Example: "", it shows No such instance

26-Mar-16 2:27:12 PM (5 ms) : SNMP V2c 26-Mar-16 2:27:12 PM (6 ms) : Custom OID 26-Mar-16 2:27:13 PM (188 ms) : SNMP Datatype: SNMP_EXCEPTION_NOSUCHINSTANCE 26-Mar-16 2:27:13 PM (192 ms) : ------- 26-Mar-16 2:27:13 PM (194 ms) : Value: No such instance (SNMP error # 223) 26-Mar-16 2:27:13 PM (197 ms) : Done

this is cause by the OID "*.1" keep increasing.

  • value keep increasing.

I found other Network Monitoring tools such as Solarwind, it only required to using OID (Example: "") instead of full OID (Example :"")

Please advise got anywhere SNMP Custom can only validate the front OID.

oid prtg snmp-custom

Created on Mar 26, 2016 6:34:47 AM

5 Replies



Dear ying7690

Did you also contact us via email? You are correct, a PRTG SNMP Custom sensor only evaluates complete OIDs.

Created on Mar 28, 2016 2:32:10 PM by  Arne Seifert [Paessler Support]



If without complete OID, can PRTG monitor it? Is it required using EXE/Script?

Created on Mar 29, 2016 8:28:32 AM



Dear ying7690

To monitor changing or incomplete OIDs, please use a custom script sensor. You could use the free Net-SNMP library to do your own SNMP queries.

Created on Mar 29, 2016 11:07:28 AM by  Arne Seifert [Paessler Support]



May i know NET-SNMP Tools installed in the Probe and available "in the path" of the Probe performing the queries.

1. I am using window server, may i know "in the path" is it means C:\Program Files (x86)

2. I perform the query below by using cmd.

C:\Windows\System32>snmpwalk -v2c  -c sbsnmp@15
SNMPv2-SMI::enterprises. = No Such Object available on this agent at this OID
C:\Windows\System32>snmpwalk -v2c  -c sbsnmp@15
SNMPv2-SMI::enterprises.2011. = Gauge32: 32

it can get the value = 32, i want to use PRTG to retrieve this value

Created on Mar 30, 2016 7:25:06 AM

Last change on Mar 30, 2016 10:42:22 AM by  Arne Seifert [Paessler Support]



Dear ying7690

A PRTG SNMP Custom sensor does not perform a walk, it reads an OID value.

If you want to use Net-SNMP in a custom sensor, you could call the Net-SNMP executable with the full path name, or add the path to Net-SNMP to the PATH environment variable. The first approach is usually preferable.

The PRTG custom sensor API is documented in the PRTG webinterface, Setup | PRTG API, tab "Custom Sensors". Your script could call the snmpwalk tool, grab the output, cut any unnecessary parts (leaving only the numeric value, in this case 32) and output that according to the custom sensor API. Using the Exe/Script standard sensor, a minimal output would look like


This example returns the number 32 and the sensor status message Okay.

Created on Mar 30, 2016 10:49:51 AM by  Arne Seifert [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.