Subject: Error "SNMP error: (noSuchName)" with data item

[GS11]

Hello!

I’m facing an issue in Zabbix related to SNMP data items. The following error appears in the server logs:

item "myswitch:swFcPortSpeed[2]" became not supported: SNMP error: (noSuchName) There is no such variable name in this MIB.

Configuration Details:

Data Item Prototype :
Name: Speed of port {#PORTN} (to {#IFNAME})
Key: swFcPortSpeed[{#PORTN}]
SNMP OID: .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35.{#SNMPINDEX}
Created Data Item :
Name: Speed of port 2
Key: swFcPortSpeed[2]
SNMP OID: .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35.3
Testing with snmp_get : When running the command:

snmp_get -v2c -c <community> <ip_address> .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35.3

I get the following error:

Reason: (noSuchName) There is no such variable name in this MIB.
Failed object: iso.3.6.1.4.1.1588.2.1.1.1.6.2.1.35.3​

The logs show periodic changes in the status of the data item:
The item becomes supported (became supported).
Then it becomes unsupported again (became not supported).





Example logs:

1490849:20250418:110038.209 item "myswitch:swFcPortSpeed[2]" became not supported: SNMP error: (noSuchName) There is no such variable name in this MIB.
1490847:20250418:112230.943 item "myswitch:swFcPortSpeed[2]" became supported
1490847:20250418:112535.662 item "myswitch:swFcPortSpeed[2]" became supported
1490847:20250418:113036.199 item "myswitch:swFcPortSpeed[2]" became not supported: SNMP error: (noSuchName) There is no such variable name in this MIB.
1490847:20250418:114739.511 item "myswitch:swFcPortSpeed[2]" became not supported: SNMP error: (noSuchName) There is no such variable name in this MIB.
1490847:20250418:121535.248 item "myswitch:swFcPortSpeed[2]" became supported
1490847:20250418:122035.954 item "myswitch:swFcPortSpeed[2]" became not supported: SNMP error: (noSuchName) There is no such variable name in this MIB.
1490847:20250418:122739.150 item "myswitch:swFcPortSpeed[2]" became supported
1490847:20250418:123237.978 item "myswitch:swFcPortSpeed[2]" became not supported: SNMP error: (noSuchName) There is no such variable name in this MIB.
1490847:20250418:124536.539 item "myswitch:swFcPortSpeed[2]" became supported
1490847:20250418:125035.180 item "myswitch:swFcPortSpeed[2]" became not supported: SNMP error: (noSuchName) There is no such variable name in this MIB.​

Discription OID .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35 from https://mibs.observium.org/mib/BROCA...#swFCPortSpeed

The desired baud rate for the port. It can have the
values of 1GB (1), 2GB (2), Auto-Negotiate (3), 4GB (4), 8GB (5),
or 10GB (6). Some of the above values may not be supported
by all type of switches.​

What I’ve Already Checked:

Confirmed that the SNMP agent on the device is working correctly and is accessible.
Verified the access rights (community string) – they are configured correctly.
Attempted to run snmpwalk for the parent OID .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35 – results are available, but the specific OID .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35.3 is missing.

Possible Causes:

The OID .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35.3 might not actually exist in the device's MIB. However, why was it discovered during LLD?
The periodic change in the item's status could be due to the dynamic nature of the OID (e.g., ports might temporarily disappear or reappear).

Questions:

Could anyone help clarify the following points:

Why does the (noSuchName) error occur?
How can I confirm whether the OID actually exists on the device?
If the OID doesn’t exist, why was it discovered during automatic discovery (LLD)?
What could cause the periodic change in the status of the data item?

I’d appreciate any advice or suggestions for further investigation!

[markfree]

Why does the (noSuchName) error occur?

The error states that the OID does not exist in your device.
This matches the OID description that says: "Some of the above values may not be supported by all type of switches".

How can I confirm whether the OID actually exists on the device?

Testing with tools like "snmpget" or "snmpwalk" (you already did so) should evidenciate that the device does not support such OID.

If the OID doesn’t exist, why was it discovered during automatic discovery (LLD)?

I guess your LLD discovers interfaces indexes, not specific items. From these discovered interfaces, item prototypes are used to create host items. If the prototypes are valid, the items are created even if they are non-existent. LLD filters and overrides should help to avoid such "not supported" items.

What could cause the periodic change in the status of the data item?

I guess your device has an unstable interface, or dynamic, that is constantly changing.

[GS11]

Thank you so much for your help markfee

I understand correctly that the OID values for specific ports, such as .1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35.(port number), are dynamic because this parameter reflects the current operational mode of the port (during data transmission). Therefore, when the port is not transmitting data, there is no corresponding OID (.1.3.6.1.4.1.1588.2.1.1.1.6.2.1.35 swFCPortSpeed) available to indicate the port's speed? The OID for the port appears only when the port is actively transmitting data, and if a request from Zabbix happens to occur during that time, the parameter is successfully retrieved.

I’m relatively new to studying and configuring Zabbix, so my knowledge in this area may not yet be deep enough. Please correct me if I’m mistaken or if there’s something I’m missing.