RMON-MIB

MIB Reference — IPNetwork Monitor · Updated September 14, 2026

All MIBsRMON-MIB

Organization: IETF RMON MIB Working Group

Last Updated: 2000-05-11

Category: Network Monitoring (RMON)

Description: Defines objects for remote network monitoring of LANs, providing packet-level statistics, history, alarms, host discovery, traffic matrix, and packet capture capabilities.

IPNetwork Monitor uses several OIDs from this MIB in network discovery and polling the applicable devices. Start monitoring RMON-MIB with a free 30-day trial of IPNetwork Monitor.

What Is RMON-MIB?

RMON-MIB is the IETF-standard Remote Network Monitoring MIB, used by network probes and switches/routers with embedded RMON agents to monitor Ethernet LAN segments independent of vendor. It exposes Ethernet statistics (packet/octet/error counters), history sampling, threshold-based alarms, host and traffic-matrix discovery, and packet capture/filter configuration. Its monitoring value lies mostly in software-level traffic health rather than hardware status - counters like etherStatsCRCAlignErrors, etherStatsUndersizePkts and etherStatsDropEvents reveal link quality and congestion issues, while alarms and events groups give proactive notification of anomalies. RMON-MIB is a standalone IETF standard with its own conformance statements (rmonCompliances, rmonGroups) but is commonly deployed alongside IF-MIB for interface context. It's typically found in managed switches, routers, and dedicated RMON probes with rmon-mib support, used for LAN traffic analysis and troubleshooting.

IPNetwork Monitor allows you to monitor SNMP objects defined in RMON-MIB. Use the built-in SNMP Monitoring Browser to explore available variables, view their current values and descriptions, and select the objects you want to monitor. You can then create SNMP monitors, configure thresholds, and receive alerts when monitored values change.

Supported Devices

  • vendor-neutral, standards-based MIB, not tied to a specific manufacturer
  • managed Ethernet switches/routers
  • dedicated RMON probes

Monitoring Examples

An administrator would poll etherStatsTable/etherStatsEntry, indexed by etherStatsIndex, to track etherStatsOctets, etherStatsPkts, etherStatsBroadcastPkts and etherStatsMulticastPkts for each monitored etherStatsDataSource (interface). A rising etherStatsCRCAlignErrors or etherStatsUndersizePkts count against a stable etherStatsPkts baseline would flag a failing cable or NIC, while a spike in etherStatsDropEvents indicates the probe itself is discarding packets due to resource limits. Comparing etherStatsOversizePkts trends across ports helps detect misconfigured MTU or jumbo-frame issues on the segment.

What Can Be Monitored

  • Ethernet packet and octet counts
  • CRC/alignment errors
  • undersized and oversized packets
  • broadcast/multicast packet rates
  • dropped events
  • traffic history and alarms
Imported Objects

From SNMPv2-CONF

MODULE-COMPLIANCE
NOTIFICATION-GROUP
OBJECT-GROUP

From SNMPv2-SMI

Counter32
Integer32
MODULE-IDENTITY
NOTIFICATION-TYPE
OBJECT-IDENTITY
OBJECT-TYPE
TimeTicks
mib-2

From SNMPv2-TC

DisplayString
TEXTUAL-CONVENTION

How to Use in IPNetwork Monitor

Example using etherHistoryUtilization OID:

Select a managed Ethernet switch, router, or dedicated RMON probe as the target host to create a monitor — the SNMP service should be up and running on it. Click New Monitor, then check SNMP Custom on the Favorites tab, click Next, and confirm the host. On the next page, click Select... to open the built-in SNMP MIB Browser and type etherHistoryUtilization into the Find box to locate it in the OID tree, selecting the specific row/instance you want to monitor since this is a table column, then select it and click OK. It reports the best estimate of mean physical-layer network utilization on this Ethernet interface during the sampling interval, in hundredths of a percent. On the monitor's Main parameters page you can set the target's SNMP port (default 161), credentials, polling interval, and other settings — see the SNMP Monitor help for details. On the State conditions and Alerting tabs, configure when the monitor should change state and trigger an alert; since this is an Integer32-type OID, Value bounds is the most useful condition here — trigger an alert if utilization exceeds 80%, since sustained high link utilization often precedes latency and packet loss. Click Finish to create the monitor; you can adjust any parameter later.
OIDs

RFC description

IETF standard MIB (RFC 2819) for Remote Network Monitoring, enabling monitoring and protocol analysis of network segments.

Start monitoring vendor-neutral, standards-based MIB, managed Ethernet switches/routers, dedicated RMON probes with a free 30-day trial of IPNetwork Monitor. Import MIBs, browse SNMP OIDs, create custom SNMP monitors, configure alerts, and monitor any SNMP-enabled network device from a single console.

Download RMON-MIB