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how can i setup an Oid with multiple snmp output value?




I want to monitor a 8 channel camera recording system. When one camera input has no video i get a number via snmp. When another i get a different number. when 2 or 3 or 4 different camera's don't work i get all different numbers.

I can get it to work with a snmpcustomsensor and alarm based on value lookup. i can enter all the different numbers but i will have to write 256 lines of code or something like that.

The supplier of the recorder told me: "For an 8 channel recorder, the OID value is range from 0 to 255. Any of the value is possible. And if you check the OID value and use the list to find the alarm channel, you need 256 commands.

A better way is to use the getbit ,and check if the alarm has been triggered and by channels. Then you just need check 8 times for an 8 channel recorder and 4 times for a 4 channel recorder.

For example, if you get a OID value 5, you can check as follow:

getbit(5,1) ☞ -1 (true)
getbit(5,2) ☞ 0 (false)
getbit(5,3) ☞ -1 (true)
getbit(5,4) ☞ 0 (false)

Then you know, channel 1 and channel 3 has alarm. "

So here is my question:

Can i use this Getbit in prtg or is there some other way to get the data without having to write a lot of codes in a lookup?

custom-sensor lookups prtg snmp

Created on Aug 7, 2019 11:39:27 AM

Last change on Aug 8, 2019 6:29:57 AM by  Stephan Linke [Paessler Support]

3 Replies



Hi ernst,

To get a better picture of your situation. Which certain (raw) values do you expect and what status is possible?

Thank you!

Best Regards,
Moritz Heller
Paessler Tech Support

Created on Aug 8, 2019 8:07:45 AM by  Moritz Heller [Paessler Support]



Created on Aug 14, 2019 12:44:35 PM

Last change on Oct 10, 2019 7:39:11 AM by  Moritz Heller [Paessler Support]



Hi Ernst,

Thank you for the information.

Have you take a look at the "BitField" option in the SNMP Lookup feature? With this function you can directly address bits and trigger status, depending on which bit is activated and which is not.
Alternatively, you can use a script that generates all lookup entries.

Best Regards,
Moritz Heller
Paessler Support

Created on Aug 15, 2019 11:16:04 AM by  Moritz Heller [Paessler Support]

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