All MIBs › FORE-IGMP-MIB
Organization: MARCONI
Last Updated: 1999-11-05
Category: ATM, Technology: Multicast, Vendor: Fore Systems (ATM)
Description: Fore Systems IGMP (Internet Group Management Protocol) MIB providing multicast group membership management objects for ATM-attached IP networks.
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What Is FORE-IGMP-MIB?
FORE-IGMP-MIB is a proprietary MIB from Fore Systems (a legacy ATM networking vendor later acquired by Marconi), covering IGMP-based IP multicast group management on ATM-attached IP networks. It exposes an IP multicast group membership table per port and an IGMP router discovery table associating router ports with VLANs, tracking which ports are members of which multicast groups and which ports lead toward multicast routers. It is used to monitor the software/protocol-state health of multicast forwarding rather than physical hardware, letting an operator verify that multicast group membership and router-port learning are correctly propagated, since an incorrect mapping would break multicast delivery. It builds on the standard IGMP protocol concepts (RFC 2236) combined with Fore's ATM/VLAN-specific port-group model. It is typically deployed on legacy Fore Systems ATM switches/routers supporting IP multicast over ATM. Engineers can download the FORE-IGMP-MIB file directly to load it into their MIB browser.
IPNetwork Monitor allows you to monitor SNMP objects defined in FORE-IGMP-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
- Fore Systems (legacy) ATM switch/router with IP multicast support
Monitoring Examples
An administrator would poll igmpIpmcTable (via igmpIpmcEntry) to confirm a given ipMulticastAddress is correctly associated with the expected ipmcPortGroup, and check igmpRouterTable's routerPortGroup per vlan to verify the multicast router port was learned correctly. A missing or wrong ipmcPortGroup mapping for an active multicast address would explain multicast traffic not reaching expected receivers.
What Can Be Monitored
- IP multicast group membership per port
- IGMP router port mapping
- multicast port-group associations per VLAN
Imported Objects
From Fore-Common-MIB
| preDot1qVlanMIB | OBJECT-IDENTITY |
From SNMPv2-SMI
| IpAddress | |
| MODULE-IDENTITY | |
| OBJECT-TYPE |
From SNMPv2-TC
| DisplayString |
OIDs
RFC description
Monitors IGMP multicast group membership and IP multicast address information on Fore Systems ethernet switches with VLAN support.
Start monitoring Fore Systems (later Marconi) ATM switch/router (IGMP multicast over ATM) 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.