Cisco Nexus 1000V MIB Quick Reference [Cisco Nexus 1000V Series Switches]

Table Of Contents

Cisco Nexus 1000V MIB Quick Reference

Information About MIBs

SNMP

SNMP Components

SNMP Versions

SNMP Messages

SNMP Manager-Agent Communication

MIB Structure

MIB Tree

Object Identifiers

Standard MIB Object

MIB Variables

Tables

MIB Information Format

MIB Access

MIB Agent Capabilities

Information About Cisco MIB Files

Cisco MIB File Directories

MIB Loading Order

ENTITY-MIB and Extensions

Extending the IF-MIB

Accessing and Downloading Cisco MIB Files

Guidelines and Limitations

Using HTTP to Access and Download the MIB Files from Cisco.com

Enabling Passive FTP

Using Passive FTP to Access and Download the MIB Files

Related Documentation

Obtaining Documentation and Submitting a Service Request

Cisco Nexus 1000V MIB Quick Reference

Text Part Number: OL-19425-01

March 7, 2011

This document describes the Cisco Nexus 1000V private or local Management Information Base (MIB) files and includes the following topics:

•Information About MIBs

•Information About Cisco MIB Files

•Accessing and Downloading Cisco MIB Files

•Related Documentation

•Obtaining Documentation and Submitting a Service Request

Information About MIBs

MIBs provide information about your network devices in a readable format as shown in Example 1.

Example 1 Standard MIB Object
sysUpTime OBJECT-TYPE
SYNTAX Time-Ticks
ACCESS read-only
STATUS mandatory
DESCRIPTION 
Time since the network management  
portion of the system was last  
re-initialized.
::= { system 1 }
SNMP

Simple Network Management Protocol (SNMP) is a communication protocol between the following interoperating systems.

•Managing systems

The most common managing system is called a network management system (NMS). The NMS runs the network management applications.

•Managed systems

Managed systems can include hosts, servers, or network components such as switches and routers.

This section includes the following topics:

•SNMP Components

•SNMP Versions

•SNMP Messages

•SNMP Manager-Agent Communication

SNMP Components

Table 1 describes the SNMP components.

Table 1 SNMP Components

SNMP Component

Description

MIB

A database of information in a standard language, the Structure of Management Information (SMI). If a component of a network device is not described in the MIB, SNMP managers and agents do not recognize that it exists.

A managed object is one of any number of specific characteristics of a managed device. Managed objects are made up of one or more object instances (identified by OID), which are essentially variables.

SNMP manager

SNMP manager receives messages from your network devices in the form of numeric strings, and uses the MIB as a code book to translate these messages into a human-readable format. Without the MIB, the message is just a meaningless string of numbers.

SNMP agent

A software component that runs on each managed device and reports information using SNMP-to-SNMP manager.

SNMP Versions

Table 2 describes the available SNMP versions.

Table 2 SNMP Versions

Version

Description

SNMPv1

Initial version of SNMP.

SNMPv2

Added support for 64-bit counters.

SNMPv3

Added increased security for access, authentication, and encryption of managed data.

SNMP Messages

Table 3 describes SNMP messages.

Table 3 SNMP Message

Message

Description

get-request

Manager-to-agent message requesting the current value of a managed object.

get-next-request

Manager-to-agent message requesting the current value of the managed object one number after the one named in the request. This is a way of walking down a table of values. The SNMP manager does not need to know the exact variable name. A sequential search finds the next variable from within the MIB.

get-bulk¹

Manager-to-agent message for retrieving large blocks of data, such as multiple rows in a table, which would otherwise require the transmission of many small blocks of data.

set-request

Manager-to-agent message that writes a new value to a managed object.

response

Agent-to-manager message in response to a GetRequest or a SetRequest. In both cases, the message reports the current value of the managed object named in the request.

trap

Agent-to-manager message reporting a change in the value of a managed object.

For more information about traps, use the SNMP-TARGET-MIB.

inform²

Agent-to-manager message notifying the agent of an event and requiring an acknowledgement.

Notifications may contain a list of MIB variables (varbinds), which are defined in the MIB. Cisco has added further clarification to some MIBs. An example of this is included in the "Extending the IF-MIB" section.

For more information about informs, use the SNMP-TARGET-MIB.

¹The get-bulk and inform commands are not a part of SNMPv1.

For information about configuring traps and informs, see the Cisco Nexus 1000V System Management Configuration Guide, Release 4.0(4)SV1(2).

SNMP Manager-Agent Communication

Figure 1 shows the communication between SNMP managers and SNMP agents.

Figure 1 SNMP Manager-Agent Communication

MIB Structure

SMI is the standard that defines how to create MIBs. SMI is described in RFC 1155.

MIBs are structured in a logical tree hierarchy. Branches of the MIB tree are organized into individual tables, which contain the managed data as leaf objects.

This section includes the following topics:

•MIB Tree

•Object Identifiers

•Standard MIB Object

•MIB Variables

•Tables

•MIB Information Format

•MIB Access

•MIB Agent Capabilities

MIB Tree

The MIB structure is organized in a tree hierarchy as shown in Figure 2. The root of the tree is unnamed and splits into the following main branches:

•Consultative Committee for International Telegraph and Telephone (CCITT)

•International Organization for Standardization (ISO)

•Joint ISO/CCITT.

Figure 2 SMI Root MIB

Object Identifiers

The numeric path from the root to the object in a MIB tree is identified by a long numeric tag or object identifier (OID) that distinguishes each object uniquely in the MIB and in SNMP messages.

When an agent sends a trap or a response, it sends a series of OIDs along with their current values.

OIDs are described in Table 4 and Figure 3.

Table 4 Structure of the Managed Object Identifier

Managed Object Identifier

Description and Example

short text string

Describes the object.

tftpHost = iso.org.dod.internet.private.enterprise.cisco.workgroup products.stack group.tftp group.tftpHost or .1.3.6.1.4.1.9.5.1.5.1. The last value is the number of the MIB variable tftpHost.

integer

Encodes the object in software, beginning at the root level and becoming more specific.

tftpHost = 1

Figure 3 SMI MIB Object Identifier

Standard MIB Object

Example 2 shows a standard MIB object.

Example 2 Standard MIB Object
sysUpTime OBJECT-TYPE
SYNTAX Time-Ticks
ACCESS read-only
STATUS mandatory
DESCRIPTION 
Time since the network management  
portion of the system was last  
re-initialized.
::= { system 1 }
Table 5 Standard MIB Object

Element

Description

OBJECT-TYPE

String that describes the object identifier (OID) of the managed object.

SYNTAX

Type of information that is stored in the MIB object.

ACCESS

Type of access that is allowed for the MIB object.

STATUS

State of the object in relation to the SNMP community.

DESCRIPTION

Reason that the MIB object exists.

MIB Variables

MIB variables are individual instances of managed objects and conform to their MIB object definition.

Tables

Tables group the instances of an object that contains multiple variables. For example, ifOperStatus.2 reports the operational state for interface 2. Tables are composed of rows, which are indexed so that SNMP can retrieve or alter an entire row with a single Get, GetNext, or Set command.

MIB tables can be thought of as spreadsheets as shown in Figure 4. The name of the table starts with the name of the MIB. If your system has three interface types, then the MIB table has three rows, identified by index numbers. Each column name starts with the name of the table, and represents a MIB object as defined by the entry node.

Figure 4 MIB Table

MIB Information Format

The format of the information in a MIB is described in the SYNTAX clause.

The Cisco NX-OS MIBs use the SNMPv2 Structure of Management Information, version 2 (SNMPv2-SMI), defined in RFC 2578. Some examples of this syntax are shown in Table 6.

Table 6 Syntax Examples

Syntax

Description

Counter32

Nonnegative integer that increases up to a maximum value, after which it rolls over to zero. For example, the variable ifInOctets, with a Counter32 syntax, counts the number of input octets on an interface.

Gauge32

Nonnegative integer that increases up to a maximum value, after which it stays fixed (no roll over).

Counter64

Nonnegative 64-bit integer that increases up to a maximum value, after which it rolls back to zero. Counter64 is used for MIB objects that can reach high values in a short period of time, for example, a packet counter for a Gigabit Ethernet port.

Integer32

Integer from -232 to 232-1.

IPAddress

Octet string that represents an IP address. For example, the variable hostConfigAddr indicates the IP address of the host that provided the host configuration file for a device.

Timeticks

Nonnegative integer that counts the hundredths of a second that have elapsed since an event. For example, the variable loctcpConnElapsed provides the length of time that a TCP connection has been established.

Example 3 is an excerpt of the information in the Interface table (ifTable) from the IF-MIB.

Example 3 IF-MIB ifTable
ifTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF IfEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "A list of interface entries.  The number of entries is
            given by the value of ifNumber."
    ::= { interfaces 2 }
ifEntry OBJECT-TYPE
    SYNTAX      IfEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "An entry containing management information applicable to a
            particular interface."
    INDEX   { ifIndex }
    ::= { ifTable 1 }
IfEntry ::=
    SEQUENCE {
        ifIndex                 InterfaceIndex,
        ifDescr                 DisplayString,
        ifType                  IANAifType,
        ifMtu                   Integer32,
        ifSpeed                 Gauge32,
        ifPhysAddress           PhysAddress,
        ifAdminStatus           INTEGER,
        ifOperStatus            INTEGER,
        ifLastChange            TimeTicks,
        ifInOctets              Counter32,
        ifInUcastPkts           Counter32,
        ifInNUcastPkts          Counter32,  -- deprecated
        ifInDiscards            Counter32,
        ifInErrors              Counter32,
        ifInUnknownProtos       Counter32,
        ifOutOctets             Counter32,
        ifOutUcastPkts          Counter32,
        ifOutNUcastPkts         Counter32,  -- deprecated
        ifOutDiscards           Counter32,
        ifOutErrors             Counter32,
        ifOutQLen               Gauge32,    -- deprecated
        ifSpecific              OBJECT IDENTIFIER -- deprecated
    }
MIB Access

The maximum access level for a MIB object is identified in the MIB MAX-ACCESS clause.
Table 7 defines MIB access levels.

Table 7 MIB Access Levels

Level

Description

read-create

You can read, modify, or create objects as rows in a table.

read-write

You can retrieve the data in a GetRequest or write new data for the object-type in a SetRequest.

read-only

You can request the data in a GetRequest, but you cannot write new data for the object-type in a SetRequest.

accessible-for-notify

You cannot read or write to this object. SNMP notifications can send this object as part of their event information.

not-accessible

The object-type is there, but you cannot request the data in a GetRequest.

You cannot read or write to this object. Table indices are an example of objects that are not accessible.

MIB Agent Capabilities

In SNMP, an agent capabilities statement documents for customers the features supported by the implementation for the associated MIB. The agent capabilities statement describes supported conformance groups and any deviations from the MIB as implemented in a specific software version. For example, the CISCO-AAA-SERVER-CAPABILITY provides the implementation details for the CISCO-AAA-SERVER-MIB, as implemented in Cisco NX-OS.

Note An agent capabilities statement may document the details for more than one software release. You need to match your software release to the corresponding AGENT-CAPABILITIES clause in the file.

Information About Cisco MIB Files

Specific MIB information for Cisco Nexus 1000V is found in the following MIB sets:

•Cisco proprietary MIBs

These MIBs are private extensions to the IETF standard MIB II.
MIB II is documented in RFC 1213.

This section includes the following topics:

•Cisco MIB File Directories

•MIB Loading Order

•ENTITY-MIB and Extensions

•Extending the IF-MIB

Cisco MIB File Directories

You can access and download Cisco MIBs and supported IETF-standard MIBs at the following URL:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

Cisco MIB files are organized into the following directories:

•SNMPv1

•SNMPv2

MIB Loading Order

Most MIBs that are not imported can be loaded in any order.

You may find information that is used in your MIB is defined in another MIB. At the beginning of every MIB file is an IMPORTS line that lists any terms used in the MIB and the RFC MIB that defines those terms. If any terms are defined in another MIB, or are IMPORTS, then this may require that the imported MIB be loaded first.

If you get an error message indicating that a MIB is undefined or not listed in IMPORTS, check the loading order and make sure that all MIBs listed in the IMPORT section are loaded first.

The following are commonly imported MIBs listed in the order in which you should load them:

•SNMPv2-SMI.my

•SNMPv2-TC.my

•SNMPv2-MIB.my

•RFC1213-MIB.my

•IF-MIB.my

•CISCO-SMI.my

•CISCO-TC.my

•CISCO-ST-TC.my

•ENTITY-MIB.my

ENTITY-MIB and Extensions

The ENTITY-MIB provides basic management and identification of physical and logical entities within a network device. Cisco NX-OS support for the ENTITY-MIB focuses on the physical entities within a device. This MIB provides details on each module, power supply, and fan tray within a switch chassis. It gives enough information to correctly map the containment of these entities within the switch, building up a chassis view.

Cisco has developed a number of private extensions to the ENTITY-MIB to provide more details for these physical entities. Each MIB extension shares the common index value, entPhysicalIndex, which allows the management application developer to link information across multiple MIBs.

Table 8 lists the Cisco MIB extensions that are linked to the ENTITY-MIB by entPhysical Index.

Table 8 ENTITY-MIB Extensions

MIB

Description

CISCO-ENTITY-ASSET-MIB

Provides manufacturing asset number and revision information per physical entity in the switch.

CISCO-ENTITY-EXT-MIB

Extends the entityPhysicalTable for modules with processors. For each of these modules, this MIB provides memory statistics and LED information.

CISCO-ENTITY-FRU-CONTROL-MIB

Manages field-replaceable units, such as power supplies, fans, and modules.

Extending the IF-MIB

The IF-MIB provides basic management status and control of interfaces and sublayers within a network device. Multiple standard and Cisco-specific MIBs use ifIndex from the IF-MIB to extend management for specific interface types. Cisco MIBs also enhance the two interface notifications, linkUp and linkDown, from the IF-MIB to provide a clearer indication of the reason for these notifications. Cisco MIBs add up to two varbinds to linkUp and linkDown as shown in Table 9.

Table 9 Varbinds Added to IF-MIB Notifications

Notification

Varbinds Added

linkUp

ifDescr

linkDown

ifDescr

For information about enabling link notifications that use these additional varbinds, see the Cisco Nexus 1000V System Management Configuration Guide, Release 4.0(4)SV1(2).

Accessing and Downloading Cisco MIB Files

You can access the Cisco MIB files.

This section includes the following topics:

•Guidelines and Limitations

•Using HTTP to Access and Download the MIB Files from Cisco.com

•Using Passive FTP to Access and Download the MIB Files

Note You can also access and download Cisco MIB files using the SNMP Object Navigator tool. You can use this tool to translate SNMP object identifiers (OIDs) into object names, search object names and descriptions, browse OID trees, and download MIB files.

Guidelines and Limitations

If your NMS cannot get requested information from a managed device, such as a Cisco switch, it is usually due to one of the following:

•The NMS does not recognize the MIB variable.

In this case, using a MIB compiler, load the MIB into the NMS.

•The agent does not support the MIB variable.

In this case, identify the version of system software you are running. Different software releases support different MIBs.

Note Cisco and IETF MIBs are updated frequently. You should download the latest MIBs from Cisco.com whenever you upgrade your software.

Using HTTP to Access and Download the MIB Files from Cisco.com

You can access and download MIB files using HTTP.

PROCEDURE

Step 1 Enter the following URL in the Address field:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

Step 2 Select and save each MIB that you need to download from the MIB support list.

Enabling Passive FTP

You can enable passive FTP in Internet Explorer.

PROCEDURE

To enable passive FTP, follow these steps:

Step 1 Open Internet Explorer, and select Tools > Internet Options.

Step 2 Click the Advanced tab on the top of the window.

Step 3 Scroll down, and check the Use Passive FTP [for firewall and DSL modem compatibility] check box.

Step 4 Click OK to save changes.

Using Passive FTP to Access and Download the MIB Files

You can access and download MIB files using passive FTP.

BEFORE YOU BEGIN

Before beginning this procedure, you must know or do the following:

•Be sure that passive FTP is enabled in your Internet Explorer.

To enable Passive FTP, see the "Enabling Passive FTP" procedure.

•You know the names of the MIBs that you need to download.

To view a list of supported MIBS, see the "Using HTTP to Access and Download the MIB Files from Cisco.com" procedure.

•Make sure that your passive FTP utility has UNIX-like commands.

PROCEDURE

Step 1 Access ftp.cisco.com using passive FTP.

Step 2 Log in with your Cisco.com username and password, or as anonymous, with your e-mail address.

Step 3 Enter cd /pub/mibs/v2/ to change directories.

Step 4 Use the get command to copy the desired files to your local system.

Step 5 Use the quit command to exit passive FTP.

Related Documentation

Cisco Nexus 1000V includes the following documents available on Cisco.com:

General Information

Cisco Nexus 1000V Release Notes, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Compatibility Information, Release 4.0(4)SV1(2)

Install and Upgrade

Cisco Nexus 1000V Software Installation Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Virtual Ethernet Module Software Installation Guide, Release 4.0(4)SV1(2)

Configuration Guides

Cisco Nexus 1000V License Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Getting Started Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Interface Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Layer 2 Switching Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Port Profile Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Quality of Service Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Security Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V System Management Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V High Availability and Redundancy Configuration Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V XML API User Guide, Release 4.0(4)SV1(2)

Programming Guide

Cisco Nexus 1000V XML API User Guide, Release 4.0(4)SV1(2)

Reference Guides

Cisco Nexus 1000V Command Reference, Release 4.0(4)SV1(2)

Cisco Nexus 1000V MIB Quick Reference

Troubleshooting and Alerts

Cisco Nexus 1000V Troubleshooting Guide, Release 4.0(4)SV1(2)

Cisco Nexus 1000V Password Recovery Guide

Cisco NX-OS System Messages Reference

Obtaining Documentation and Submitting a Service Request

For information about obtaining documentation, submitting a service request, and gathering additional information, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation.

Subscribe to the What's New in Cisco Product Documentation as a Really Simple Syndication (RSS) feed and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free service and Cisco currently supports RSS version 2.0.

Cisco and the Cisco Logo are trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and other countries. A listing of Cisco's trademarks can be found at www.cisco.com/go/trademarks. Third party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1005R)

Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.

© 2009 Cisco Systems, Inc. All rights reserved.

Cisco Nexus 1000V Series Switches

Cisco Nexus 1000V MIB Quick Reference

Hierarchical Navigation

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Table Of Contents

Cisco Nexus 1000V MIB Quick Reference

Information About MIBs

SNMP

SNMP Components

SNMP Versions

SNMP Messages

SNMP Manager-Agent Communication

MIB Structure

MIB Tree

Object Identifiers

Standard MIB Object

MIB Variables

Tables

MIB Information Format

MIB Access

MIB Agent Capabilities

Information About Cisco MIB Files

Cisco MIB File Directories

MIB Loading Order

ENTITY-MIB and Extensions

Extending the IF-MIB

Accessing and Downloading Cisco MIB Files

Guidelines and Limitations

Using HTTP to Access and Download the MIB Files from Cisco.com

PROCEDURE

Enabling Passive FTP

PROCEDURE

Using Passive FTP to Access and Download the MIB Files

BEFORE YOU BEGIN

PROCEDURE

Related Documentation

General Information

Install and Upgrade

Configuration Guides

Programming Guide

Reference Guides

Troubleshooting and Alerts

Obtaining Documentation and Submitting a Service Request

© 2009 Cisco Systems, Inc. All rights reserved.

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