CNT21-MIB :: cnt2IfInUnknownProtos

MIB Reference — IPNetwork Monitor · Updated September 14, 2026

All MIBsCNT21-MIBcnt2IfInUnknownProtos

cnt2IfInUnknownProtos

Module: CNT21-MIB

OID (symbolic): CNT21-MIB::cnt2IfInUnknownProtos

OID (numeric): 1.3.6.1.4.1.333.2.1.2.2.1.16

Node type: OBJECT-TYPE

Type: Counter32

Access: read-only

Description: The number of packets received via the interface which were discarded because of an unknown or unsupported protocol.

What is cnt2IfInUnknownProtos?

This Counter32 counts packets received on the interface that were discarded because of an unknown or unsupported protocol. An administrator uses a nonzero value here to detect unexpected protocol traffic arriving on a port that wasn't configured to handle it. For example, cnt2IfInUnknownProtos incrementing on an interface meant to carry only IP traffic could reveal stray legacy protocol frames still arriving.

Examples

Walk all instances (SNMPv2c):

snmpwalk -v2c -c public <target> 1.3.6.1.4.1.333.2.1.2.2.1.16
snmpwalk -v2c -c public <target> CNT21-MIB::cnt2IfInUnknownProtos

Get a specific instance (index 1):

snmpget -v2c -c public <target> 1.3.6.1.4.1.333.2.1.2.2.1.16.1
snmpget -v2c -c public <target> CNT21-MIB::cnt2IfInUnknownProtos.1

Start monitoring CNT 2.1-series Fibre Channel SAN switch (legacy) with a free 30-day trial of IPNetwork Monitor. Create custom SNMP monitor using the CNT21-MIB::cnt2IfInUnknownProtos OID value, configure state conditions and alerts, and monitor any CNT 2.1-series Fibre Channel SAN switch (legacy) from a single console.

OID Breakdown

Upper-level ancestors (9 from the standard OID tree / other modules)
Numeric OIDNameModule
1isoLANART-AGENT
1.3orgAirPair-MIB
1.3.6dodAirPair-MIB
1.3.6.1internetAirPair-MIB
1.3.6.1.4privateAirPair-MIB
1.3.6.1.4.1enterprisesAirPair-MIB
1.3.6.1.4.1.333cntCNT2-MIB
1.3.6.1.4.1.333.2cnt2CNT2-MIB
1.3.6.1.4.1.333.2.1cnt2Mib2CNT2-MIB
Numeric OIDNameModule
1.3.6.1.4.1.333.2.1.2cnt2InterfacesCNT21-MIB
1.3.6.1.4.1.333.2.1.2.2cnt2IfTableCNT21-MIB
1.3.6.1.4.1.333.2.1.2.2.1cnt2IfEntryCNT21-MIB
1.3.6.1.4.1.333.2.1.2.2.1.16cnt2IfInUnknownProtosCNT21-MIB