SNMP extension 2.0 INVALID_CONFIG_ERROR error

[eranga]

Hi All,

We have a custom Dynatrace extension built using the v2 framework to retrieve NetScaler SDX metrics via SNMP. Recently, we encountered the following error:

“INVALID_CONFIG_ERROR: Text-type OID used as metric value”

This error occurs for the following OID references:

• systemCpuUsage (1.3.6.1.4.1.5951.6.2.24)
• systemMemoryUsage (1.3.6.1.4.1.5951.6.2.25)
• systemDiskUsage (1.3.6.1.4.1.5951.6.2.26)

We tested these OIDs using snmpget and received the following result: (example)

SNMPv2-SMI::enterprises.5951.6.2.25.0 = STRING: "52.94"

Has anyone experienced a similar issue or know what might be causing it?

[Peter_Youssef]

Hello @eranga 

For the custom extension

Dynatrace Doc:

•  data-sources/snmp-extensions 
• snmp#activate-extension 
• eec-custom-configuration 

KR,

Peter.

[Peter_Youssef]

Hello @eranga 

As an alternative solution:

• If it's possible to use the developed extension by Dynatrace from Dynatrace Hub would be good.

And in such case:

1. Revisit citrix-netscaler-sdx.
2. Review Citrix error-messages and configuration with NetScaler team.
3. First of all you should validate the FW configurations are conducted properly between the assigned EAGs and the end points.
4. Ensure the endpoints are configured properly as per app owner inputs.
5. Disable SSL certificate check.

BR,

Peter.

[PetrVlacil]

I cannot test it myself as I do not have a netscaler available but I would say that problem is that this OID is string. Also snmpget output says that this OID is of STRING type. So it cannot be used as a metric value.

There is no free accessible version of MIB file with above mentioned OIDs. I was able to find MIBs containing OIDs only up to systemCustomID (1.3.6.1.4.1.5951.6.2.23).

Would it be possible to use different OID that is not STRING?

[AntonioSousa]

@eranga, @PetrVlacil 

SNMP doesn't have float types. So anything like that has to be a string. There are some cases where you have decimal points definition, but that is way harder to sort out...

[AntonioSousa]

@eranga  BTW,

seems to be a very recent MIB. None of the usual browsers I use show it:

• https://mibs.observium.org/mib/SDX-ROOT-MIB/
• https://oidref.com/1.3.6.1.4.1.5951.6.2
• https://mibbrowser.online/mibdb_search.php?mib=MIB

No reason to doubt your snmpget though 😁

[p_devulapalli · Accepted solution]

Hi @eranga , I think the SNMP variables that you are using are the right once, but unfortunately they are being returned as string instead of a gauge or a count (see below link similar issue)

https://community.citrix.com/forums/topic/253266-issue-with-oid-13614159514114120-on-netscaler-adc-s...

Here is a similar previous discussion about proving metrics out of String OID's

https://community.dynatrace.com/t5/Open-Q-A/SNMP-extension-v2-problems/m-p/176388

Extension framework currently supports metric payloads in the gauge or count value  formats only. Would be good to raise it as a product idea/enhancement .