CISCOSB-rlFft

MIB Reference — IPNetwork Monitor · Updated September 09, 2026

All MIBsCISCOSB-rlFft

Organization: Cisco Small Business

Last Updated: 2004-06-01

Category: Vendor: Cisco

Description: Manages fast forwarding table (FFT) configuration and lookup on Cisco Small Business devices.

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What Is CISCOSB-rlFft?

CISCOSB-rlFft is a Cisco Small Business (formerly Layer3/Marvell-based 'rl' switch platform) proprietary MIB managing the Fast Forwarding Table (FFT), an internal hardware lookup table used for accelerated Layer 3 (IP/IPX) forwarding decisions on small-business switches. It exposes configuration objects controlling FFT capacity, dynamic entry support, subnet-based lookup support, aging timeout behavior, and threshold boundaries (red/yellow) used to signal table utilization pressure, along with separate FFT instances for IP, IPX, and multicast forwarding. Its monitoring value centers on hardware forwarding resource health: administrators can track rlInetMaxFftNumber against actual utilization to see how close the forwarding table is to capacity, and watch the rlIpFftRedBoundary/rlIpFftYellowBoundary thresholds to catch early warning signs of table exhaustion, which would cause the switch to fall back to slower software forwarding and degrade throughput. It is a self-contained Cisco Small Business proprietary MIB not derived from a broader IETF standard. It is typically deployed on Cisco Small Business (SG/SF-series, formerly Layer3) switches in small-to-midsize business networks doing hardware-accelerated IP routing. Engineers can download the CISCOSB-rlFft file directly to load it into their MIB browser.

IPNetwork Monitor allows you to monitor SNMP objects defined in CISCOSB-rlFft. 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

  • Cisco Small Business (SG/SF-series) switch

Monitoring Examples

An administrator would poll rlInetFftNumTable to see current fast-forwarding entry counts against rlInetMaxFftNumber, and compare that against the configured rlIpFftRedBoundary and rlIpFftYellowBoundary thresholds to detect when the FFT is nearing capacity. If the entry count crosses the yellow boundary and continues climbing toward the red boundary, this would reveal that the switch is close to exhausting hardware forwarding capacity and will start punting traffic to slower CPU-based forwarding. Checking rlInetFftAgingTimeout alongside rlIpFftUnknownAddrMsgUsed helps confirm stale entries are being aged out properly to free up table space.

What Can Be Monitored

  • fast forwarding table entry count
  • FFT capacity/threshold (red/yellow boundary)
  • FFT aging timeout
  • dynamic/subnet FFT support status
  • per-protocol (IP/IPX) FFT utilization
Imported Objects

From CISCOSB-MIB

switch001MODULE-IDENTITY

From INET-ADDRESS-MIB

InetAddress
InetAddressPrefixLength
InetAddressType

From SNMPv2-SMI

IpAddress
MODULE-IDENTITY
OBJECT-TYPE
Unsigned32

From SNMPv2-TC

DisplayString
PhysAddress
RowStatus
TEXTUAL-CONVENTION
TruthValue
OIDs

RFC description

Cisco Small Business vendor-private MIB for real-time FFT (signal processing) or filter management.

Start monitoring Cisco Small Business (SG/SF-series) switch 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 CISCOSB-rlFft