Cisco ONS 15600 Troubleshooting Guide, Release 5.0
Chapter 5, SNMP
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SNMP

Table Of Contents

SNMP

5.1  SNMP Overview

5.2  Basic SNMP Components

5.3  SNMP External Interface Requirement

5.4  SNMP Version Support

5.5  SNMP Message Types

5.6  SNMP Management Information Bases

5.7  SNMP Trap Content

5.7.1  Generic and IETF Traps

5.7.2  Variable Trap Bindings

5.8  SNMP Community Names


SNMP


This chapter explains Simple Network Management Protocol (SNMP) as implemented by the Cisco ONS 15600.

For SNMP set up information, refer to the Cisco ONS 15600 Procedure Guide.

Chapter topics include:

SNMP Overview

Basic SNMP Components

SNMP External Interface Requirement

SNMP Version Support

SNMP Message Types

SNMP Management Information Bases

SNMP Trap Content

SNMP Community Names

5.1  SNMP Overview

SNMP is an application-layer communication protocol that allows ONS 15600 network devices to exchange management information among these systems and with other devices outside the network. Through SNMP, network administrators can manage network performance, find and solve network problems, and plan network growth.

The ONS 15600 uses SNMP for asynchronous event notification to a network management system (NMS). ONS SNMP implementation uses standard Internet Engineering Task Force (IETF) management information bases (MIBs) to convey node-level inventory, fault, and performance management information for generic read-only management of DS-1, DS-3, SONET, and Ethernet technologies. SNMP allows a generic SNMP manager such as HP OpenView Network Node Manager (NNM) or Open Systems Interconnection (OSI) NetExpert to be utilized for limited management functions.

The Cisco ONS 15600s support SNMP Version 1 (SNMPv1) and SNMP Version 2c (SNMPv2c). Both of these versions share many features, but SNMPv2c includes additional protocol operations and 64-bit performance monitoring support. This chapter describes both versions and gives SNMP configuration parameters for the ONS 15600.

Figure 5-1 illustrates the basic layout idea of an SNMP-managed network.

Figure 5-1 Basic Network Managed by SNMP

5.2  Basic SNMP Components

In general terms, an SNMP-managed network consists of a management system, agents, and managed devices.

A management system such as HP OpenView executes monitoring applications and controls managed devices. Management systems execute most of the management processes and provide the bulk of memory resources used for network management. A network might be managed by one or more management systems. Figure 5-2 illustrates the relationship between the network manager, SNMP agent, and the managed devices.

Figure 5-2 Example of the Primary SNMP Components

An agent (such as SNMP) residing on each managed device translates local management information data, such as performance information or event and error information caught in software traps, into a readable form for the management system. Figure 5-3 illustrates SNMP agent get-requests that transport data to the network management software.

Figure 5-3 Agent Gathering Data from a MIB and Sending Traps to the Manager

The SNMP agent captures data from management information bases, or MIBs, which are device parameter and network data repositories, or from error or change traps.

A managed element—such as a router, access server, switch, bridge, hub, computer host, or network element (such as an ONS 15600)—is accessed through the SNMP agent. Managed devices collect and store management information, making it available via SNMP to other management systems having the same protocol compatibility.

5.3  SNMP External Interface Requirement

Since all SNMP requests come from a third-party application, the only external interface requirement is that a third-part SNMP client application can upload RFC 3273 SNMP MIB variables in the etherStatsHighCapacityTable, etherHistoryHighCapacityTable, or mediaIndependentTable.

5.4  SNMP Version Support

The ONS 15600 supports SNMPv1 and SNMPv2c traps and get requests. The ONS 15600 SNMP MIBs define alarms, traps, and status. Through SNMP, NMS applications can query a management agent for data from functional entities such as Ethernet switches and SONET multiplexers using a supported MIB.

5.5  SNMP Message Types

The ONS 15600 SNMP agent communicates with an SNMP management application using SNMP messages. Table 5-1 describes these messages.

Table 5-1 ONS 15600 SNMP Message Types 

Operation
Description

get-request

Retrieves a value from a specific variable.

get-next-request

Retrieves the value following the named variable; this operation is often used to retrieve variables from within a table. With this operation, an SNMP manager does not need to know the exact variable name. The SNMP manager searches sequentially to find the needed variable from within the MIB.

get-response

Replies to a get-request, get-next-request, get-bulk-request, or set-request sent by an NMS.

get-bulk-request

Fills the get-response with up to the max-repetition number of get-next interactions, similar to a get-next-request.

set-request

Provides remote network monitoring (RMON) MIB.

trap

Indicates that an event has occurred. An unsolicited message is sent by an SNMP agent to an SNMP manager.


5.6  SNMP Management Information Bases

Table 5-2 lists the IETF-standard MIBs implemented in the ONS 15600 SNMP agents.

First compile the MIBs in Table 5-2. Next, compile the mibs in the order given in Table 5-3.


Caution If you do not compile MIBs in the correct order, one or more might not compile correctly.

Table 5-2 IETF Standard MIBs Implemented in the ONS 15600 System 

RFC 1 Number
Module Name
Title/Comments

IANAifType-MIB.mib

Internet Assigned Numbers Authority (IANA) ifType

1213

RFC1213-MIB-rfc1213.mib

Management Information Base for Network

1907

SNMPV2-MIB-rfc1907.mib

Management of TCP/IP-based Internets: MIB-II
Management Information Base for Version 2 of the Simple Network Management Protocol (SNMPv2)

1253

RFC1253-MIB-rfc1253.mib

OSPF Version 2 Management Information Base

1493

BRIDGE-MIB-rfc1493.mib

Definitions of Managed Objects for Bridges
(This defines MIB objects for managing MAC bridges based on the IEEE 802.1D-1990 standard between Local Area Network [LAN] segments.)

2819

RMON-MIB-rfc2819.mib

Remote Network Monitoring Management Information Base

2737

ENTITY-MIB-rfc2737.mib

Entity MIB (Version 2)

2233

IF-MIB-rfc2233.mib

Interfaces Group MIB using SMIv2

2358

EtherLike-MIB-rfc2358.mib

Definitions of Managed Objects for the Ethernet-like Interface Types

2493

PerfHist-TC-MIB-rfc2493.mib

Textual Conventions for MIB Modules Using Performance History Based on 15 Minute Intervals (not applicable to the ONS 15600)

2495

DS1-MIB-rfc2495.mib

Definitions of Managed Objects for the DS1, E1, DS2 and E2 Interface Types (not applicable to the ONS 15600)

2496

DS3-MIB-rfc2496.mib

Definitions of Managed Object for the DS3/E3 Interface Type (not applicable to the ONS 15600)

2558

SONET-MIB-rfc2558.mib

Definitions of Managed Objects for the SONET/SDH Interface Type

2674

P-BRIDGE-MIB-rfc2674.mib Q-BRIDGE-MIB-rfc2674.mib

Definitions of Managed Objects for Bridges with Traffic Classes, Multicast Filtering and Virtual LAN Extensions

3273

HC-RMON-MIB

The MIB module for managing remote monitoring device implementations, augmenting the original RMON MIB as specified in RFC 2819 and RFC 1513 and RMON-2 MIB as specified in RFC 2021

1 RFC = Request for Comment


Each ONS system is shipped with a software CD containing applicable proprietary MIBs. The MIBs in Table 5-3 are used with the ONS 15600.

Table 5-3 ONS 15600 Proprietary MIBs 

MIB Number
Module Name

1

CERENT-GLOBAL-REGISTRY.mib

2

CERENT-TC.mib

3

CERENT-454.mib

4

CERENT-GENERIC.mib



Note If you cannot compile the proprietary MIBs correctly, log into the Cisco Technical Assistance Center (TAC) at http://www.cisco.com/techsupport or call Cisco TAC (800) 553-2447.


5.7  SNMP Trap Content

The ONS 15600 generates all alarms and events, such as raises and clears, as SNMP traps. These contain the following information:

Object IDs that uniquely identify each event with information about the generating entity (the slot or port; synchronous transport signal [STS] and Virtual Tributary [VT]; bidirectional line switched ring [BLSR], Spanning Tree Protocol [STP], etc.).

Severity and service effect of the alarm (critical, major, minor, or event; service-affecting or non-service affecting).

Date and time stamp showing when the alarm occurred.

5.7.1  Generic and IETF Traps

The ONS 15600 supports the generic IETF traps listed in Table 5-4.

Table 5-4 ONS 15600 Generic Traps 

Trap
From RFC No. MIB
Description

coldStart

RFC1213-MIB

Agent up, cold start.

warmStart

RFC1213-MIB

Agent up, warm start.

newRoot

RFC1493/
BRIDGE-MIB

Sending agent is the new root of the spanning tree.

topologyChange

RFC1493/
BRIDGE-MIB

A port in a bridge has changed from Learning to Forwarding or Forwarding to Blocking.

entConfigChange

RFC2037/
ENTITY-MIB

The entLastChangeTime value has changed.

risingAlarm

RFC2819/
RMON-MIB

The SNMP trap that is generated when an alarm entry crosses the rising threshold and the entry generates an event that is configured for sending SNMP traps.

fallingAlarm

RFC2819/
RMON-MIB

The SNMP trap that is generated when an alarm entry crosses the falling threshold and the entry generates an event that is configured for sending SNMP traps.


5.7.2  Variable Trap Bindings

Each SNMP trap contains variable bindings that are used to create the MIB tables. Variable bindings for the ONS 15600 are listed in Table 5-5. For each group (such as Group A), all traps within the group are associated with all of its variable bindings.

Table 5-5 15600 SNMPv2 Trap Variable Bindings 

Group
Trap Name(s) Associated with
(Variable Binding Number)
SNMPv2 Variable Bindings
Description

A

dsx1LineStatusChange (from RFC 2495)

(1)

dsx1LineStatus

This variable indicates the line status of the interface. It contains loopback, failure, received alarm and transmitted alarm information.

(2)

dsx1LineStatusLastChange

The value of MIB II's sysUpTime object at the time this DS1 entered its current line status state. If the current state was entered prior to the last proxy-agent re-initialization, the value of this object is zero.

(3)

cerentGenericNodeTime

The time that an event occurred.

(4)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

(5)

snmpTrapAddress

The address of the SNMP trap.

B

dsx3LineStatusChange (from RFC 2496)

(1)

dsx3LineStatus

This variable indicates the line status of the interface. It contains loopback state information and failure state information.

(2)

dsx3LineStatusLastChange

The value of MIB II's sysUpTime object at the time this DS3/E3 entered its current line status state. If the current state was entered prior to the last re-initialization of the proxy-agent, then the value is zero.

(3)

cerentGenericNodeTime

The time that an event occurred.

(4)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

(5)

snmpTrapAddress

The address of the SNMP trap.

C

coldStart (from RFC 1907)

(1)

cerentGenericNodeTime

The time that an event occurred.

warmStart (from RFC 1907)

(2)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

newRoot (from RFC)

(3)

snmpTrapAddress

The address of the SNMP trap.

topologyChange (from RFC)

 

entConfigChange (from RFC 2737)

 

authenticationFailure (from RFC 1907)

 

D1

risingAlarm (from RFC 2819)

(1)

alarmIndex

This variable uniquely identifies each entry in the alarm table. When an alarm in the table clears, the alarm indexes change for each alarm listed.

 

(2)

alarmVariable

The object identifier of the variable being sampled.

 

(3)

alarmSampleType

The method of sampling the selected variable and calculating the value to be compared against the thresholds.

 

(4)

alarmValue

The value of the statistic during the last sampling period.

 

(5)

alarmRisingThreshold

When the current sampled value is greater than or equal to this threshold, and the value at the last sampling interval was less than this threshold, a single event is generated. A single event is also generated if the first sample after this entry is greater than or equal to this threshold.

 

(6)

cerentGenericNodeTime

The time that an event occurred.

 

(7)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

 

(8)

snmpTrapAddress

The address of the SNMP trap.

D2

fallingAlarm (from RFC 2819)

(1)

alarmIndex

This variable uniquely identifies each entry in the alarm table. When an alarm in the table clears, the alarm indexes change for each alarm listed.

 

(2)

alarmVariable

The object identifier of the variable being sampled.

 

(3)

alarmSampleType

The method of sampling the selected variable and calculating the value to be compared against the thresholds.

 

(4)

alarmValue

The value of the statistic during the last sampling period.

 

(5)

alarmFallingThreshold

When the current sampled value is less than or equal to this threshold, and the value at the last sampling interval was greater than this threshold, a single event is generated. A single event is also generated if the first sample after this entry is less than or equal to this threshold.

 

(6)

cerentGenericNodeTime

The time that an event occurred.

 

(7)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

 

(8)

snmpTrapAddress

The address of the SNMP trap.

E

failureDetectedExternalToTheNE (from CERENT-454-mib)

(1)

cerentGenericNodeTime

The time that an event occurred.

(2)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

(3)

cerentGenericAlarmObjectType

The entity that raised the alarm. The NMS should use this value to decide which table to poll for further information about the alarm.

(4)

cerentGenericAlarmObjectIndex

Every alarm is raised by an object entry in a specific table. This variable is the index of objects in each table; if the alarm is interface-related, this is the index of the interface in the interface table.

(5)

cerentGenericAlarmSlotNumber

The slot of the object that raised the alarm. If a slot is not relevant to the alarm, the slot number is zero.

(6)

cerentGenericAlarmPortNumber

The port of the object that raised the alarm. If a port is not relevant to the alarm, the port number is zero.

(7)

cerentGenericAlarmLineNumber

The object line that raised the alarm. If a line is not relevant to the alarm, the line number is zero.

(8)

cerentGenericAlarmObjectName

The TL1-style user-visible name that uniquely identifies an object in the system.

(9)

cerentGenericAlarmAdditionalInfo

Additional information for the alarm object. In the current version of the MIB, this object contains provisioned description for alarms that are external to the NE. If there is no additional information, the value is zero.

(10)

snmpTrapAddress

The address of the SNMP trap.

F

performanceMonitorThresholdCrossingAlert (from CERENT-454-mib)

(1)

cerentGenericNodeTime

The time that an event occurred.

 

(2)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

 

(3)

cerentGenericAlarmObjectType

The entity that raised the alarm. The NMS should use this value to decide which table to poll for further information about the alarm.

 

(4)

cerentGenericAlarmObjectIndex

Every alarm is raised by an object entry in a specific table. This variable is the index of objects in each table; if the alarm is interface-related, this is the index of the interface in the interface table.

 

(5)

cerentGenericAlarmSlotNumber

The slot of the object that raised the alarm. If a slot is not relevant to the alarm, the slot number is zero.

 

(6)

cerentGenericAlarmPortNumber

The port of the object that raised the alarm. If a port is not relevant to the alarm, the port number is zero.

 

(7)

cerentGenericAlarmLineNumber

The object line that raised the alarm. If a line is not relevant to the alarm, the line number is zero.

 

(8)

cerentGenericAlarmObjectName

The TL1-style user-visible name that uniquely identifies an object in the system.

 

(9)

cerentGenericThresholdMonitorType

This object indicates the type of metric being monitored.

 

(10)

cerentGenericThresholdLocation

Indicates whether the event occurred at the near- or far end.

 

(11)

cerentGenericThresholdPeriod

Indicates the sampling interval period.

 

(12)

cerentGenericThresholdSetValue

The value of this object is the threshold provisioned by the NMS.

 

(13)

cerentGenericThresholdCurrentValue

 
 

(14)

cerentGenericThresholdDetectType

 
   

(15)

snmpTrapAddress

The address of the SNMP trap.

G

All other traps (from CERENT-454-MIB) not listed above

(1)

cerentGenericNodeTime

The time that an event occurred.

 

(2)

cerentGenericAlarmState

The alarm severity and service-affecting status. Severities are Minor, Major, and Critical. Service-affecting statuses are Service-Affecting and Non-Service Affecting.

 

(3)

cerentGenericAlarmObjectType

The entity that raised the alarm. The NMS should use this value to decide which table to poll for further information about the alarm.

 

(4)

cerentGenericAlarmObjectIndex

Every alarm is raised by an object entry in a specific table. This variable is the index of objects in each table; if the alarm is interface-related, this is the index of the interface in the interface table.

 

(5)

cerentGenericAalrmSlotNumber

The slot of the object that raised the alarm. If a slot is not relevant to the alarm, the slot number is zero.

 

(6)

cerentGenericAlarmPortNumber

The port of the object that raised the alarm. If a port is not relevant to the alarm, the port number is zero.

 

(7)

cerentGenericAlarmLineNumber

The object line that raised the alarm. If a line is not relevant to the alarm, the line number is zero.

 

(8)

cerentGenericAlarmObjectName

The TL1-style user-visible name that uniquely identifies an object in the system.

 

(9)

snmpTrapAddress

The address of the SNMP trap.


5.8  SNMP Community Names

Community names are used to group SNMP trap destinations. All ONS 15600 trap destinations can be provisioned as part of SNMP communities in Cisco Transport Controller (CTC). When community names are assigned to traps, the ONS 15600 treats the request as valid if the community name matches one that is provisioned in CTC. In this case, all agent-managed MIB variables are accessible to that request. If the community name does not match the provisioned list, SNMP drops the request.