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Table Of Contents

BGP MIB Support Enhancements

Contents

Prerequisites for BGP MIB Support Enhancements

Restrictions for BGP MIB Support Enhancements

BGP MIB Support Enhancements Overview

BGP FSM Transition Change Support

BGP Route Received Route Support

BGP Prefix Threshold Notification Support

VPNv4 Unicast Address Family Route Support

cbgpPeerTable Support

How to Enable BGP MIB Support on a Router

Configuration Examples for BGP MIB Support Enhancements

Configuring BGP MIB Support Enhancements: Example

Verifying BGP MIB Support Enhancements: Example

Where to Go Next

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Command Reference

snmp-server enable traps bgp

BGP MIB Support Enhancements

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The BGP MIB Support Enhancements feature enhances or introduces the following capabilities for Simple Network Management (SNMP) monitoring of Border Gateway Protocol (BGP) using the CISCO-BGP4-MIB:

•BGP FSM Transition Change Support—Enhances support for notification of BGP Finite State Machine (FSM) transition changes.

•BGP Route Received Route Support—Introduces the capability to query for the total number of routes received by a BGP neighbor.

•BGP Prefix Threshold Notification Support—Introduces the capability to send notifications when the prefix limit for a BGP peer has been reached.

•VPNv4 Unicast Address Family Route Support—Enhances the cbgpRouteTable object to provide support for SNMP GET operations on VPNv4 unicast routes.

Release	Modification
12.0(26)S	This feature was introduced.
12.3(7)T	This feature was integrated into Cisco IOS Release 12.3(7)T.
12.2(25)S	This feature was integrated into Cisco IOS Release 12.2(25)S.

Feature History for the BGP MIB Support Enhancements Feature

Finding Support Information for Platforms and Cisco IOS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.

Contents

•Prerequisites for BGP MIB Support Enhancements

•Restrictions for BGP MIB Support Enhancements

•BGP MIB Support Enhancements Overview

•How to Enable BGP MIB Support on a Router

•Configuration Examples for BGP MIB Support Enhancements

•Additional References

•Command Reference

Prerequisites for BGP MIB Support Enhancements

•SNMP must be enabled on the router before notifications (traps) can be configured or before SNMP GET operations can be performed.

Restrictions for BGP MIB Support Enhancements

•All enhancements that are introduced by this feature are supported by only the CISCO-BGP4-MIB.

BGP MIB Support Enhancements Overview

The BGP MIB Support Enhancements feature introduces support in the CISCO-BGP4-MIB for new SNMP notifications. To enable BGP support for the enhancement described in this document, use the snmp-server enable traps bgp command in global configuration mode. The following sections describe the objects and notifications (traps) that have been enhanced by this feature:

•BGP FSM Transition Change Support

•BGP Route Received Route Support

•BGP Prefix Threshold Notification Support

•VPNv4 Unicast Address Family Route Support

•cbgpPeerTable Support

BGP FSM Transition Change Support

The cbgpRouteTable was enhanced to support BGP Finite State Machine (FSM) transition state changes.

The cbgpFsmStateChange object was introduced to allow the you to configure SNMP notifications (traps) for all FSM transition state changes. This notification contains the following MIB objects:

•bgpPeerLastError

•bgpPeerState

•cbgpPeerLastErrorTxt

•cbgpPeerPrevState

The cbgpBackwardTransition object has also been enhanced to support all BGP FSM transition state changes. This object is sent each time the FSM moves to either a higher or lower numbered state. This notification contains the following MIB objects:

•bgpPeerLastError

•bgpPeerState

•cbgpPeerLastErrorTxt

•cbgpPeerPrevState

The enhancement to the snmp-server enable bgp traps privileged EXEC command allows you to enable the newly introduced traps individually or together with the existing FSM backward transition and established state traps as defined in RFC 1657.

BGP Route Received Route Support

The cbgpRouteTable object has been enhanced to support the total number of routes received by a BGP neighbor. The following new MIB object was introduced to support this enhancement:

•cbgpPeerAddrFamilyPrefixTable

Routes are indexed by the address-family identifier (AFI) or subaddress-family identifier (SAFI). The prefix information displayed in this table can also viewed in the output of the show ip bgp command.

BGP Prefix Threshold Notification Support

The cbgpPrefixMaxThresholdExceed and cbgpPrfefixMaxThresholdClear objects were introduced to allow you to poll for the total number of routes received by a BGP peer.

The cbgpPrefixMaxThresholdExceed object was introduced to allow you to configure SNMP notifications to be sent when the prefix count for a BGP session has exceeded the configured value. This notification is configured on a per address family basis. The prefix threshold is configured with the neighbor maximum-prefix command. This notification contains the following MIB objects:

•cbgpPeerPrefixAdminLimit

•cbgpPeerPrefixThreshold

The cbgpPrfefixMaxThresholdClear object was introduced to allow you to configure SNMP notifications to be sent when the prefix count drops below the clear trap limit. This notification is configured on a per address family basis. This notification contains the following objects:

•cbgpPeerPrefixAdminLimit

•cbgpPeerPrefixClearThreshold

Notifications are sent when the prefix count drops below the clear trap limit for an address family under a BGP session after the cbgpPrefixMaxThresholdExceed notification is generated. The clear trap limit is calculated by subtracting 5 percent from the maximum prefix limit value configured with the neighbor maximum-prefix command. This notification will not be generated if the session goes down for any other reason after the cbgpPrefixMaxThresholdExceed is generated.

VPNv4 Unicast Address Family Route Support

The cbgpRouteTable object was enhanced to allow you to configure SNMP GET operations for VPNv4 unicast address-family routes.

The following MIB object was introduced to allow you to query for multiple BGP capabilities (for example, route refresh, multiprotocol BGP extensions, graceful restart, etc):

•cbgpPeerCapsTable

The following new MIB object was introduced to allow you to query for IPv4 and VPNv4 address family routes:

•cbgpPeerAddrFamilyTable

Each route is indexed by peer address, prefix, and prefix length. This object indexes BGP routes by the AFI and then by the SAFI. The AFI table is the primary index, and the SAFI table is the secondary index. Each BGP speaker maintains a local Routing Information Base (RIB) for each supported AFI and SAFI combination.

cbgpPeerTable Support

The cbgpPeerTable has been modified to support the enhancements described in this document. The following new table objects are supported in the CISCO-BGP-MIB.my:

•cbgpPeerLastErrorTxt

•cbgpPeerPrevState

The following table objects are not supported. The status of theses objects is listed as deprecated. However, these objects are not operational:

•cbgpPeerPrefixAccepted

•cbgpPeerPrefixDenied

•cbgpPeerPrefixLimit

•cbgpPeerPrefixAdvertised

•cbgpPeerPrefixSuppressed

•cbgpPeerPrefixWithdrawn

How to Enable BGP MIB Support on a Router

SNMP notifications can be configured on the router and GET operations can be performed from an external management station only after BGP SNMP support is enabled.

SUMMARY STEPS

1. enable

2. configure terminal

3. snmp-server enable traps bgp [state-changes {[all] [backward-trans] [limited]}] | [threshold prefix]

4. exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	snmp-server enable traps bgp [state-changes {[all] [backward-trans] [limited]}] | [threshold prefix] Example: Router# snmp-server enable traps bgp	Enables BGP support for SNMP operations. Entering this command with no keywords or arguments enables support for all BGP events. The state-changes keyword is used to enable support for FSM transition events. •The all keyword enables support for FSM transitions events. •The backward-trans keyword enables support only for backward transition state change events. •The limited keyword enables support for backward transition state changes and established state events. The threshold prefix keywords are used to enable notifications when the configured maximum prefix limit is reached on the specified peer.
Step 4	exit Example: Router(config)# exit	Exits global configuration mode, and enters privileged EXEC mode.

Configuration Examples for BGP MIB Support Enhancements

The following examples show how to configure and verify the BGP MIB Support Enhancements feature:

•Configuring BGP MIB Support Enhancements: Example

•Verifying BGP MIB Support Enhancements: Example

Configuring BGP MIB Support Enhancements: Example

The following example enables SNMP support for all supported BGP events:

Router(config)# snmp-server enable traps bgp

Verifying BGP MIB Support Enhancements: Example

The following verification example shows that SNMP support for BGP is enabled and shown the running-config file:

Router# show run | include snmp-server

snmp-server enable traps bgp

Where to Go Next

For more information about SNMP and SNMP operations, refer to the "Configuring SNMP Support" section of the Cisco IOS Configuration Fundamentals and Network Management Configuration Guide, Release 12.3.

Additional References

The following sections provide references related to BGP MIB Support Enhancements.

Related Documents

Related Topic	Document Title
BGP commands	•Cisco IOS IP Command Reference, Volume 2 of 4: Routing Protocols, Release 12.3T
BGP configuration tasks	•Cisco IOS IP Configuration Guide, Release 12.3

Standards

Standards	Title
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.	—

MIBs

MIBs	MIBs Link
•CISCO-BGP4-MIB	To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL: http://www.cisco.com/go/mibs

RFCs

RFCs	Title
RFC 1657	Definitions of Managed Objects for the Fourth Version of the Border Gateway Protocol (BGP-4) using SMIv2
RFC 1771	A Border Gateway Protocol 4 (BGP-4)
RFC 2547	BGP/MPLS VPNs
RFC 2842	Capabilities Advertisement with BGP-4
RFC 2858	Multiprotocol Extensions for BGP-4
RFC 2918	Route Refresh Capability for BGP-4

Technical Assistance

Description	Link
Technical Assistance Center (TAC) home page, containing 30,000 pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.	http://www.cisco.com/public/support/tac/home.shtml

Command Reference

This feature uses a modified command. All commands used with this feature are documented in the Cisco IOS command reference publications.

•snmp-server enable traps bgp  

snmp-server enable traps bgp

To enable Border Gateway Protocol (BGP) support for Simple Network Management Protocol (SNMP) operations on a router, use the snmp-server enable traps bgp command in global configuration mode. To disable BGP support for SNMP operations, use the no form of this command.

snmp-server enable traps bgp [state-changes {[all] [backward-trans] [limited]}] | [threshold prefix]

no snmp-server enable traps bgp [state-changes {[all] [backward-trans] [limited]}] | [threshold prefix]

Syntax Description

state-changes	(Optional) Enables support for notifications for FSM state change events.
all	(Optional) Enables support for Cisco specific notifications for all FSM state change events.
backward-trans	(Optional) Enables support for Cisco specific notifications for backward transition events.
limited	(Optional) Enables support for notifications for standard backward transition and established events.
threshold prefix	(Optional) Enables support for notifications for Cisco specific trap for prefix threshold events.

Defaults

SNMP notifications are disabled by default.

Command Modes

Global configuration

Command History

Release	Modification
12.1(3)T	This command was introduced for the Cisco AS5300 and Cisco AS5800.
12.0(26)S 12.3(7)T 12.2(25)S	The following keywords were integrated in Cisco IOS Release 12.0(26)S, 12.3(7)T, and 12.2(25)S: •state-changes •all •backward-trans •limited •threshold prefix

Usage Guidelines

SNMP notifications can be sent as notifications (traps) or inform requests. This command enables both notifications and inform requests.

This command controls (enables or disables) Border Gateway Protocol server state change notifications, as defined in the BGP4-MIB (enterprise 1.3.6.1.2.1.15.7). The notifications types are:

•bgpEstablished

•bgpBackwardsTransition

For a complete description of BGP notifications and additional MIB functions, see the BGP4-MIB.my file, available through the Cisco FTP site at ftp://www.cisco.com/public/mibs/v2/.

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Note You may experience problems in the output that is generated by the SNMP version 1 BGP4-MIB that is available for download at ftp://ftp.cisco.com/pub/mibs/v1/BGP4-MIB-V1SMI. This MIB is not compliant with RFC-1908 specifications. The OID becomes truncated when state changes on an SNMP version 1 monitored BGP peer are sent to the monitoring agent. The enterprise OID is sent as 1.3.6.1.2.1.15 instead of 1.3.6.1.2.1.15.7. This problem causes the monitoring agent to display the OID incorrectly. IANA and IETF are the governing bodies that control this MIB. We have submitted corrections and are awaiting publication. In the mean time, we recommend that you use the SNMP version 2 BGP4-MIB or the CISCO-BGP4-MIB that is supported by this feature.

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The snmp-server enable traps bgp command is used in conjunction with the snmp-server host command. Use the snmp-server host command to specify which host or hosts receive SNMP notifications. To send SNMP notifications, you must configure at least one snmp-server host command.

Examples

The following example enables the router to send BGP state change informs to the host at the address myhost.cisco.com using the community string defined as public:

Router(config)# snmp-server enable traps bgp

Router(config)# snmp-server host myhost.cisco.com informs version 2c public

Related Commands

Command	Description
snmp-server host	Specifies the recipient of an SNMP notification operation.
snmp-server trap-source	Specifies the interface that an SNMP trap should originate from.

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