CTIF-EXT-MIB

MIB Reference — IPNetwork Monitor · Updated September 09, 2026

All MIBsCTIF-EXT-MIB

Category: Network Interfaces, Vendor: Cabletron/Enterasys

Description: Extends standard IF-MIB with Cabletron-specific interface attributes including duplex mode and flow control status.

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What Is CTIF-EXT-MIB?

CTIF-EXT-MIB is a Cabletron Systems (predecessor to Enterasys) proprietary MIB that extends the standard IETF IF-MIB with additional per-port interface attributes for Cabletron network switches and hubs. It exposes interface configuration and capability data - duplex mode, locally administered address, port capability flags, and redundancy status - along with device-level clock and board-map information. It supports monitoring hardware/software status indirectly: ctIfDuplex reveals negotiated link duplex state (useful for spotting duplex mismatches), ctIfRedundancy shows redundant-link health, and comDeviceBoardMap exposes the chassis's board/module inventory. It explicitly depends on and extends the standard IETF IF-MIB, reusing its interface indexing. It is typically deployed on legacy Cabletron/Enterasys switches and hubs, where CTIF-EXT-MIB SNMP monitoring provides finer per-port diagnostics than IF-MIB alone.

IPNetwork Monitor allows you to monitor SNMP objects defined in CTIF-EXT-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

  • Cabletron Systems switches and hubs
  • Enterasys network switches (legacy Cabletron-derived)

Monitoring Examples

ctIfTable/ctIfEntry extend ifTable with fields such as ctIfDuplex, ctIfLAA, and ctIfCapability; an admin polling ctIfDuplex across ports can catch a duplex mismatch that is causing excessive collisions on a link. ctIfRedundancy flags whether a port belongs to a redundant pair, useful for confirming failover readiness before a planned link test. comDeviceBoardMap and comDeviceTime/comDeviceDate expose the chassis board layout and onboard clock, which an operator would check to confirm module inventory and time sync during troubleshooting, while ctIfPortCnt/ctIfNumber report total port counts on the device.

What Can Be Monitored

  • per-port duplex mode
  • port capability flags
  • redundant link pairing status
  • device board/module inventory
  • device clock/date
  • total port/interface count
Imported Objects

From CTRON-MIB-NAMES

ctronMib2OBJECT-IDENTITY

From IF-MIB

ifIndexOBJECT-TYPE

From RFC-1212

OBJECT-TYPE

From RFC1155-SMI

Counter

From RFC1213-MIB

DisplayString
OIDs

RFC description

Computer Telephony Integration Framework extension MIB for telephony system management.

Start monitoring Cabletron/Enterasys switch/hub (legacy, per-port IF-MIB extension) 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 CTIF-EXT-MIB