All MIBs › Usr-bridge-MIB
Category: CommWorks/3Com Access Equipment
Description: Manages bridge forwarding, spanning tree, and port filtering on CommWorks/3Com access equipment.
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What Is Usr-bridge-MIB?
This is a bridging MIB for U.S. Robotics/CommWorks access equipment (the product line later absorbed into 3Com), extending standard 802.1D-style bridge management for these WAN access devices. It exposes bridge forwarding behavior, spanning tree state, and port-level filtering rules used to build a Layer 2 bridged topology across the device's ports. In monitoring terms it lets an operator check the software/hardware status of bridging on the device - specifically whether individual ports are in a healthy forwarding state versus stuck in a spanning-tree blocking or disabled state, a key sign of a physical link or loop problem. It closely parallels (and likely extends) the standard IETF BRIDGE-MIB (dot1dBridge) structures for forwarding database and spanning tree tables. It is typically deployed on CommWorks/3Com remote access routers and concentrators that bridge LAN and WAN segments together. Engineers can download the Usr-bridge-MIB file directly to load it into their MIB browser.
IPNetwork Monitor allows you to monitor SNMP objects defined in Usr-bridge-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
- CommWorks/3Com remote access routers
- U.S. Robotics access concentrators
Monitoring Examples
No specific object names were provided for this module, so rather than invent any, a realistic scenario would follow standard dot1dBridge/dot1dStp conventions: poll the bridge forwarding database and per-port spanning tree state tables to confirm a port is in the forwarding state rather than stuck in blocking, which would reveal an active spanning-tree loop or a misconfigured filter rule on that port.
What Can Be Monitored
- bridge port forwarding state
- spanning tree topology status
- port filtering rules
- bridge forwarding database entries
This MIB depends on
Related MIBs
Imported Objects
From RFC-1212
| OBJECT-TYPE |
From RFC1155-SMI
| Counter | |
| TimeTicks |
From RFC1213-MIB
| DisplayString |
From USR-DEFINITIONS-MIB
| UsrConfigStatus | |
| UsrUserName | |
| usrBridge | OBJECT-IDENTITY |
OIDs
| OID symbolic | OID numeric | Type | Access | Description |
|---|---|---|---|---|
| usrBRBase | 1.3.6.1.4.1.429.4.14.1 | |||
| MAC usrBRBaseBridgeAddress | 1.3.6.1.4.1.429.4.14.1.1 | MacAddress | read-only | The MAC address used by this bridge when it must be referred to in a unique fashion. It is recommended that this be the numerically smallest MAC address of all ports that belong to this bridge. However it is only required to be unique. When concatenated with usrBRStpPriority a unique BridgeIdentifier is formed which is used in the Spanning Tree Protocol. |
| INT usrBRBaseNumPorts | 1.3.6.1.4.1.429.4.14.1.2 | INTEGER | read-only | The number of ports controlled by this bridging entity. |
| INT usrBRBaseType | 1.3.6.1.4.1.429.4.14.1.3 | INTEGER | read-only | Indicates what type of bridging this bridge can perform. If a bridge is actually performing a certain type of bridging this will be indicated by entries in the port table for the given type. |
| INT usrBRBaseStaticMacsOnly | 1.3.6.1.4.1.429.4.14.1.4 | INTEGER | read-write | Indicates whether the bridge will forward all (non-local) packets or just those to and from the stations whose MAC addresses are specified in the Access List (BRStaticTable). |
| INT usrBRBaseAgingTime | 1.3.6.1.4.1.429.4.14.1.5 | INTEGER | read-write | The timeout period in seconds for aging out dynamically learned forwarding information. 802.1D-1990 recommends a default of 300 seconds. |
| CTR usrBRBaseLearnedEntryDiscards | 1.3.6.1.4.1.429.4.14.1.6 | Counter | read-only | The total number of Forwarding Database entries, which have been or would have been learnt, but have been discarded due to a lack of space to store them in the Forwarding Database. If this counter is increasing, it indicates that the Forwarding Database is regularly becoming full (a condition which has unpleasant performance effects on the subnetwork). If this counter has a significant value but is not presently increasing, it indicates that the problem has been occurring but is not persistent. |
| STR usrBRBaseCfgFileName | 1.3.6.1.4.1.429.4.14.1.7 | DisplayString | read-write | The name of a ConfigFile to read/write permanent database records. If the value of this object is an empty string, then the Bridge process uses the default name `@file://BridgeFile.cfg'. |
| USR usrBRBaseCFMSaveStatus | 1.3.6.1.4.1.429.4.14.1.8 | UsrConfigStatus | read-write | Setting the value of this object to `save' causes the values of the Bridge Base Group entries to be written out to the current Bridge config file. While the new config file is being written, the Bridge process will set the value of this flag set to `saving''. Any attempts to set the value while it is not `normal' (i.e. the file is currently being written to the config file) while result in a badValue error being returned. Setting the value to `normal' will result in no action. |
| INT usrBRBaseWanToWanForwarding | 1.3.6.1.4.1.429.4.14.1.9 | INTEGER | read-write | Indicates whether the bridge will forward packets received on a wide area port to other wide area ports. |
| usrBRBasePortTable | 1.3.6.1.4.1.429.4.14.1.10 | not-accessible | A table that contains generic information about every port that is associated with this bridge. Transparent, source-route, and srt ports are included. | |
| usrBRBasePortEntry | 1.3.6.1.4.1.429.4.14.1.10.1 | not-accessible | A list of information for each port of the bridge. | |
| INT usrBRBasePortId | 1.3.6.1.4.1.429.4.14.1.10.1.1 | INTEGER | not-accessible | The value of the instance of the ifIndex object, defined in MIB-II, for the interface corresponding to this port. |
| STR usrBRBaseIfName | 1.3.6.1.4.1.429.4.14.1.10.1.2 | DisplayString | read-only | The interface name of the port for which this entry contains bridge management information. |
| INT usrBRBasePortIfIndex | 1.3.6.1.4.1.429.4.14.1.10.1.3 | INTEGER | read-only | The value of the instance of the ifIndex object, defined in MIB-II, for the interface corresponding to this port. |
| CTR usrBRBasePortInFrames | 1.3.6.1.4.1.429.4.14.1.10.1.4 | Counter | read-only | The number of frames that have been received by this port from its segment. Note that a frame received on the interface corresponding to this port is only counted by this object if and only if it is for a protocol being processed by the local bridging function, including bridge management frames. |
| CTR usrBRBasePortOutFrames | 1.3.6.1.4.1.429.4.14.1.10.1.5 | Counter | read-only | The number of frames that have been transmitted by this port to its segment. Note that a frame transmitted on the interface corresponding to this port is only counted by this object if and only if it is for a protocol being processed by the local bridging function, including bridge management frames. |
| CTR usrBRBasePortInDiscards | 1.3.6.1.4.1.429.4.14.1.10.1.6 | Counter | read-only | Count of valid frames received which were discarded (i.e., filtered) by the Forwarding Process. |
| INT usrBRBaseBridgeFirewallMode | 1.3.6.1.4.1.429.4.14.1.11 | INTEGER | read-write | The Firewall mode determines how the bridge forwards packets when the Platform is enabled as a Bridge/Router. If set to 0, all enabled routed protocols are not forwarded over bridge ports. If set to 1, only unicasts not destined to the BRouter's are forwarded, and if set to 2, pkts defined in (1) and Broadcasts are forwarded. |
| usrBRStp | 1.3.6.1.4.1.429.4.14.2 | |||
| INT usrBRStpMode | 1.3.6.1.4.1.429.4.14.2.1 | INTEGER | read-write | Indicates whether the Spanning Tree Protocol is enabled for this unit. |
| INT usrBRStpProtocolSpecification | 1.3.6.1.4.1.429.4.14.2.2 | INTEGER | read-only | An indication of what version of the Spanning Tree Protocol is being run. The value 'decLb100(2)' indicates the DEC LANbridge 100 Spanning Tree protocol. IEEE 802.1d implementations will return 'ieee8021d(3)'. If future versions of the IEEE Spanning Tree Protocol are released that are incompatible with the current version a new value will be defined. |
| INT usrBRStpPriority | 1.3.6.1.4.1.429.4.14.2.3 | INTEGER | read-write | The value of the write-able portion of the Bridge ID, i.e., the first two octets of the (8 octet long) Bridge ID. The other (last) 6 octets of the Bridge ID are given by the value of usrBRBaseBridgeAddress. |
| TIK usrBRStpTimeSinceTopologyChange | 1.3.6.1.4.1.429.4.14.2.4 | TimeTicks | read-only | The time (in hundredths of a second) since the last time a topology change was detected by the bridge entity. |
| CTR usrBRStpTopChanges | 1.3.6.1.4.1.429.4.14.2.5 | Counter | read-only | The total number of topology changes detected by this bridge since the management entity was last reset or initialized. |
| BRI usrBRStpDesignatedRoot | 1.3.6.1.4.1.429.4.14.2.6 | BridgeId | read-only | The bridge identifier of the root of the spanning tree as determined by the Spanning Tree Protocol as executed by this node. This value is used as the Root Identifier parameter in all Configuration Bridge PDUs originated by this node. |
| INT usrBRStpRootCost | 1.3.6.1.4.1.429.4.14.2.7 | INTEGER | read-only | The cost of the path to the root as seen from this bridge. |
| INT usrBRStpRootPort | 1.3.6.1.4.1.429.4.14.2.8 | INTEGER | read-only | The port number of the port which offers the lowest cost path from this bridge to the root bridge. |
| TIM usrBRStpMaxAge | 1.3.6.1.4.1.429.4.14.2.9 | Timeout | read-only | The maximum age of Spanning Tree Protocol information learned from the network on any port before it is discarded, in units of hundredths of a second. This is the actual value that this bridge is currently using. |
| TIM usrBRStpHelloTime | 1.3.6.1.4.1.429.4.14.2.10 | Timeout | read-only | The amount of time between the transmission of Configuration bridge PDUs by this node on any port when it is the root of the spanning tree or trying to become so, in units of hundredths of a second. This is the actual value that this bridge is currently using. |
| INT usrBRStpHoldTime | 1.3.6.1.4.1.429.4.14.2.11 | INTEGER | read-only | This time value determines the interval length during which no more than two Configuration bridge PDUs shall be transmitted by this node, in units of hundredths of a second. |
| TIM usrBRStpForwardDelay | 1.3.6.1.4.1.429.4.14.2.12 | Timeout | read-only | This time value, measured in units of hundredths of a second, controls how fast a port changes its spanning state when moving towards the Forwarding state. The value determines how long the port stays in each of the Listening and Learning states, which precede the Forwarding state. This value is also used, when a topology change has been detected and is underway, to age all dynamic entries in the Forwarding Database. [Note that this value is the one that this bridge is currently using, in contrast to usrBRStpBridgeForwardDelay which is the value that this bridge and all others would start using if/when this bridge were to become the root.] |
| TIM usrBRStpBridgeMaxAge | 1.3.6.1.4.1.429.4.14.2.13 | Timeout | read-write | The value that all bridges use for MaxAge when this bridge is acting as the root. Note that 802.1D-1990 specifies that the range for this parameter is related to the value of usrBRStpBridgeHelloTime. The granularity of this timer is specified by 802.1D-1990 to be 1 second. An agent may return a badValue error if a set is attempted to a value which is not a whole number of seconds. |
| TIM usrBRStpBridgeHelloTime | 1.3.6.1.4.1.429.4.14.2.14 | Timeout | read-write | The value that all bridges use for HelloTime when this bridge is acting as the root. The granularity of this timer is specified by 802.1D- 1990 to be 1 second. An agent may return a badValue error if a set is attempted to a value which is not a whole number of seconds. |
| TIM usrBRStpBridgeForwardDelay | 1.3.6.1.4.1.429.4.14.2.15 | Timeout | read-write | The value that all bridges use for ForwardDelay when this bridge is acting as the root. Note that 802.1D-1990 specifies that the range for this parameter is related to the value of usrBRStpBridgeMaxAge. The granularity of this timer is specified by 802.1D-1990 to be 1 second. An agent may return a badValue error if a set is attempted to a value which is not a whole number of seconds. |
| usrBRStpPortTable | 1.3.6.1.4.1.429.4.14.2.16 | not-accessible | A table that contains port-specific information for the Spanning Tree Protocol. | |
| usrBRStpPortEntry | 1.3.6.1.4.1.429.4.14.2.16.1 | not-accessible | A list of information maintained by every port about the Spanning Tree Protocol state for that port. | |
| INT usrBRStpPortId | 1.3.6.1.4.1.429.4.14.2.16.1.1 | INTEGER | not-accessible | The value of the instance of the ifIndex object, defined in MIB-II, for the interface corresponding to this port. |
| INT usrBRStpPort | 1.3.6.1.4.1.429.4.14.2.16.1.2 | INTEGER | read-only | The port number of the port for which this entry contains Spanning Tree Protocol management information. |
| INT usrBRStpPortPriority | 1.3.6.1.4.1.429.4.14.2.16.1.3 | INTEGER | read-only | The value of the priority field which is contained in the first (in network byte order) octet of the (2 octet long) Port ID. The other octet of the Port ID is given by the value of usrBRStpPort. |
| INT usrBRStpPortState | 1.3.6.1.4.1.429.4.14.2.16.1.4 | INTEGER | read-only | The port's current state as defined by application of the Spanning Tree Protocol. This state controls what action a port takes on reception of a frame. For ports which are disabled (see usrBRStpPortEnable), this object will have a value of disabled(1). |
| INT usrBRStpPortEnable | 1.3.6.1.4.1.429.4.14.2.16.1.5 | INTEGER | read-only | The enabled/disabled status of the port. |
| INT usrBRStpPortPathCost | 1.3.6.1.4.1.429.4.14.2.16.1.6 | INTEGER | read-only | The contribution of this port to the path cost of paths towards the spanning tree root which include this port. 802.1D-1990 recommends that the default value of this parameter be in inverse proportion to the speed of the attached LAN. |
| BRI usrBRStpPortDesignatedRoot | 1.3.6.1.4.1.429.4.14.2.16.1.7 | BridgeId | read-only | The unique Bridge Identifier of the Bridge recorded as the Root in the Configuration BPDUs transmitted by the Designated Bridge for the segment to which the port is attached. |
| INT usrBRStpPortDesignatedCost | 1.3.6.1.4.1.429.4.14.2.16.1.8 | INTEGER | read-only | The path cost of the Designated Port of the segment connected to this port. This value is compared to the Root Path Cost field in received bridge PDUs. |
| BRI usrBRStpPortDesignatedBridge | 1.3.6.1.4.1.429.4.14.2.16.1.9 | BridgeId | read-only | The Bridge Identifier of the bridge which this port considers to be the Designated Bridge for this port's segment. |
| OCT usrBRStpPortDesignatedPort | 1.3.6.1.4.1.429.4.14.2.16.1.10 | OCTET STRING | read-only | The Port Identifier of the port on the Designated Bridge for this port's segment. |
| CTR usrBRStpPortForwardTransitions | 1.3.6.1.4.1.429.4.14.2.16.1.11 | Counter | read-only | The number of times this port has transitioned from the Learning state to the Forwarding state. |
| usrBRTp | 1.3.6.1.4.1.429.4.14.3 | |||
| usrBRTpFdbTable | 1.3.6.1.4.1.429.4.14.3.1 | not-accessible | This table that contains information about unicast entries for which the bridge has forwarding and/or filtering information. This information is used by the transparent bridging function in determining how to propagate a received frame. | |
| usrBRTpFdbEntry | 1.3.6.1.4.1.429.4.14.3.1.1 | not-accessible | Information about a specific unicast MAC address for which the bridge has some forwarding and/or filtering information. | |
| MAC usrBRTpFdbAddress | 1.3.6.1.4.1.429.4.14.3.1.1.1 | MacAddress | not-accessible | A unicast MAC address for which the bridge has forwarding and/or filtering information. |
| INT usrBRTpFdbPort | 1.3.6.1.4.1.429.4.14.3.1.1.2 | INTEGER | read-only | Either the value '0', or the port number of the port on which a frame having a source address equal to the value of the corresponding instance of usrBRTpFdbAddress has been seen. A value of '0' indicates that the port number has not been learned but that the bridge does have some forwarding/filtering information about this address (e.g. in the usrBRStaticTable). Implementors are encouraged to assign the port value to this object whenever it is learned even for addresses for which the corresponding value of usrBRTpFdbStatus is not learned(3). |
| INT usrBRTpFdbStatus | 1.3.6.1.4.1.429.4.14.3.1.1.3 | INTEGER | read-only | The status of this entry. The meanings of the values are: other(1) : none of the following. This would include the case where some other MIB object (not the corresponding instance of usrBRTpFdbPort, nor an entry in the usrBRStaticTable) is being used to determine if and how frames addressed to the value of the corresponding instance of usrBRTpFdbAddress are being forwarded. invalid(2) : this entry is not longer valid (e.g., it was learned but has since aged-out), but has not yet been flushed from the table. learned(3) : the value of the corresponding instance of usrBRTpFdbPort was learned, and is being used. self(4) : the value of the corresponding instance of usrBRTpFdbAddress represents one of the bridge's addresses. The corresponding instance of usrBRTpFdbPort indicates which of the bridge's ports has this address. mgmt(5) : the value of the corresponding instance of usrBRTpFdbAddress is also the value of an existing instance of usrBRStaticAddress. |
| CTR usrBRTpFdbRxPkts | 1.3.6.1.4.1.429.4.14.3.1.1.4 | Counter | read-only | Number of packets received from this MAC station. |
| CTR usrBRTpFdbRxOctets | 1.3.6.1.4.1.429.4.14.3.1.1.5 | Counter | read-only | Number of bytes received from this MAC station. |
| CTR usrBRTpFdbRxFiltPkts | 1.3.6.1.4.1.429.4.14.3.1.1.6 | Counter | read-only | Number of packets received from this MAC station that were filtered (not forwarded). |
| CTR usrBRTpFdbRxFwdPkts | 1.3.6.1.4.1.429.4.14.3.1.1.7 | Counter | read-only | Number of packets received from this MAC station that were forwarded. |
| CTR usrBRTpFdbTxPkts | 1.3.6.1.4.1.429.4.14.3.1.1.8 | Counter | read-only | Number of packets forwarded to this MAC station. |
| CTR usrBRTpFdbTxOctets | 1.3.6.1.4.1.429.4.14.3.1.1.9 | Counter | read-only | Number of bytes forwarded to this MAC station. |
| usrBRStaticMAC | 1.3.6.1.4.1.429.4.14.4 | |||
| usrBRStaticMACTable | 1.3.6.1.4.1.429.4.14.4.1 | not-accessible | This table contains MAC addresses of stations whose traffic is allowed to pass from one bridge port to another. Note that this table is used to filter traffic only when BRBaseStaticMacsOnly is set to Enabled. | |
| usrBRStaticMACEntry | 1.3.6.1.4.1.429.4.14.4.1.1 | not-accessible | A MAC Address that identifies a station whose traffic is allowed to pass from one bridge port to another. | |
| MAC usrBRStaticMACAddress | 1.3.6.1.4.1.429.4.14.4.1.1.1 | MacAddress | not-accessible | The MAC Address of the station allowed access through the bridge. |
| USR usrBRStaticMACUser | 1.3.6.1.4.1.429.4.14.4.1.1.2 | UsrUserName | read-write | Name of the user to be associated with the specified MAC Address. |
| INT usrBRStaticStatus | 1.3.6.1.4.1.429.4.14.4.1.1.3 | INTEGER | read-write | Setting this variable to delete removes the entry. |
RFC description
SNMP extension MIB providing Linux bridge port information and IEEE 802.1D bridge management via SNMP.
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