Cisco NX-OS MIB Quick Reference

Table Of Contents

Cisco Nexus 7000 Series NX-OS MIB Quick Reference

Information About MIBs and Network Management

Accessing MIB Variables Through SNMP

SNMP Traps and Informs

Interpreting the MIB Structure

Object Identifiers

Tables

SYNTAX Clause

MAX-ACCESS Clause

AGENT-CAPABILITIES

Information About Cisco MIB Files

Cisco MIB File Directories

MIB Loading Order

Accessing and Downloading Cisco MIB Files

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

Using Passive FTP to Access and Download the MIB Files

Understanding the ENTITY-MIB and Extensions

Extending the IF-MIB

Related Documentation

Documentation Feedback

Obtaining Documentation and Submitting a Service Request

Cisco Nexus 7000 Series NX-OS MIB Quick Reference

---

Date: August , 2013

This document describes the private, or local, Management Information Base (MIB) files for the Cisco NX-OS software.

This document provides the following information:

•Information About MIBs and Network Management

•Information About Cisco MIB Files

•Accessing and Downloading Cisco MIB Files

•Understanding the ENTITY-MIB and Extensions

•Extending the IF-MIB

•Documentation Feedback

•Obtaining Documentation and Submitting a Service Request

Information About MIBs and Network Management

The Cisco NX-OS MIB list includes Cisco proprietary MIBs and many other Internet Engineering Task Force (IETF) standard MIBs. These standard MIBs are defined in Requests for Comments (RFCs). To find specific MIB information, you must examine the Cisco proprietary MIB structure and related IETF-standard MIBs supported by the Cisco NX-OS.

Network management takes place between two major types of systems: those systems in control, called managing systems, and those systems that managing systems observe and control, called managed systems. The most common managing system is called a network management system (NMS). Managed systems can include hosts, servers, or network components such as switches and routers.

To promote interoperability, cooperating systems must adhere to a common framework and a common language, called a protocol. In the Internet-standard management framework, that protocol is the Simple Network Management Protocol (SNMP).

The exchange of information between managed network devices and a robust NMS is essential for reliable performance of a managed network. Because some devices have a limited ability to run management software, most of the computer processing burden is assumed by the NMS. The NMS runs the network management applications, such as Cisco Data Center Network Manager (DCNM), that present management information to network managers and other users.

In a managed device, specialized low-impact software modules, called agents, access information about the device and make it available to the NMS. Managed devices maintain values for a number of variables and report those, as required, to the NMS. For example, an agent might report such data as the number of bytes and packets sent or received by the device or the number of broadcast messages sent and received. In SNMP, each of these variables is referred to as a managed object. A managed object is anything that can be managed or anything that an agent can access and report back to the NMS. All managed objects are contained in the MIB, which is a database of the managed objects.

An NMS can control a managed device by sending a request to an agent of that managed device, requiring the device to change the value of one or more of its variables. The managed devices can respond to requests such as set or get. The NMS uses the set request to control the device. The NMS uses the get requests to monitor the device. The set and get requests are synchronous events, which means that the NMS initiates the activity, and the SNMP agent responds.

The managed device can send asynchronous events, or SNMP notifications, to the NMS to inform the NMS of some recent event. SNMP notifications (traps or informs) are included in many MIBs and allow the NMS to less frequently send get requests to the managed devices.

This section includes the following topics:

•Accessing MIB Variables Through SNMP

•SNMP Traps and Informs

•Interpreting the MIB Structure

Accessing MIB Variables Through SNMP

You can access the Cisco MIB variables through SNMP. The SNMP system consists of three parts: the SNMP manager, the SNMP agent, and the MIB. You can compile Cisco MIBs with your network management software. If SNMP is configured on a device, the SNMP agent responds to MIB-related queries sent by the NMS.

Table 1-1 describes the SNMP operations.

Table 1-1 SNMP Operations 

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.1
get-bulk2	Retrieves 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	Stores a value in a specific variable.
response	Replies to the above commands sent by an NMS and to the informs sent by an agent.
trap	Sends an unsolicited message by an SNMP agent to an SNMP manager indicating that some event has occurred.
inform2	Sends an unsolicited message by an SNMP agent to an SNMP manager indicating that some event has occurred. This operation differs from a trap in that an acknowledgement is required from the manager.

1 With this operation, an SNMP manager does not need to know the exact variable name. A sequential search finds the next variable from within the MIB. 2 The get-bulk and inform commands are not a part of SNMPv1.

SNMPv1 was the initial version of the protocol. SNMPv2 added support for 64-bit counters, and SNMPv3 added increased security for access, authentication, and encryption of managed data.

SNMP Traps and Informs

You can configure Cisco NX-OS to send notifications to SNMP managers when particular events occur. You can send these notifications as traps or inform requests. Traps are unreliable because the receiver does not send any acknowledgment when it receives a trap. The sender cannot determine if the trap was received. However, an SNMP manager that receives an inform request acknowledges the message with an SNMP response. If the sender never receives a response, the inform request can be sent again. Informs are more likely to reach their intended destinations than traps.

Notifications may contain a list of MIB variables (varbinds) that clarify that the status is relayed by the notification. The list of varbinds associated with a notification is included in the notification definition in the MIB. In the case of standard MIBs, Cisco has enhanced some notifications with additional varbinds that further clarify the cause of the notification. See the "Extending the IF-MIB" section for an example of these extensions in the IF-MIB.

Use the SNMP-TARGET-MIB to obtain more information on trap destinations and inform requests. See the Cisco NX-OS System Management CLI Configuration Guide for more information on configuring traps and informs.

---

Note You must enable most notifications through the CLI. For more information, see the Cisco Nexus 7000 Series System Management Configuration Guide, Release 5.x.

---

Interpreting the MIB Structure

A MIB presents the managed data in a logical tree hierarchy, using an IETF standard syntax called the Structure of Management Information (SMI). Branches of this MIB tree are organized into individual tables, which contain the managed data as leaf objects.

This section includes the following topics:

•Object Identifiers

•Tables

•SYNTAX Clause

•MAX-ACCESS Clause

•AGENT-CAPABILITIES

Object Identifiers

The MIB structure is logically represented by a tree hierarchy. The root of the tree is unnamed and splits into three main branches: Consultative Committee for International Telegraph and Telephone (CCITT), International Organization for Standardization (ISO), and joint ISO/CCITT.

These branches and those branches that fall below each category have short text strings and integers to identify them. Text strings describe object names, while integers allow computer software to create compact, encoded representations of the names.

Each MIB variable is assigned with an object identifier. The object identifier is the sequence of numeric labels on the nodes along a path from the root to the object. For example, the MIB variable tftpHost is indicated by the number 1. The object identifier for tftpHost is 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.

Tables

When network management protocols use names of MIB objects in messages, each name has an appended suffix. This suffix is called an instance identifier. It identifies one occurrence of the associated MIB object. For simple scalar objects, the instance identifier 0 refers to the instance of the object with that name (for example, sysUpTime.0).

A MIB also can contain tables of related objects. For example, ifOperStatus is a MIB object inside the ifTable from the IF-MIB. It reports the operational state for an interface on a device. Because devices may have more than one interface, it is necessary to have more than one instance of ifOperStatus. This instance value is added to the end of the MIB object as the instance identifier (for example, ifOperStatus.2 reports the operational state for interface number 2).

Each object in a table is constructed with a set of clauses defined by the SMI. These clauses include the SYNTAX clause, MAX-ACCESS clause, STATUS clause, and DESCRIPTION clause.

An excerpt of the information in the VSAN table (known as vsanTable) from CISCO-VSAN-MIB follows:

vsanTable OBJECT-TYPE

        SYNTAX     SEQUENCE OF VsanEntry

        MAX-ACCESS not-accessible

        STATUS     current

        DESCRIPTION

        "A table of VSANs configured on this device."

		::= { vsanConfiguration 3 }

vsanEntry OBJECT-TYPE

        SYNTAX     VsanEntry

        MAX-ACCESS not-accessible

        STATUS     current

        DESCRIPTION

               "An entry (conceptual row) in the vsanTable."

        INDEX { vsanIndex }

        ::= { vsanTable 1 }

VsanEntry ::= SEQUENCE {

        vsanIndex                 VsanIndex,

        vsanName                  SnmpAdminString,

In the example, vsanTable contains two variables: vsanIndex and vsanName. (There are more values in the actual vsanTable.) The index for this table is the ID of the VSAN, or vsanIndex. With n number of VSANs configured, n rows are present in the table. If you want to retrieve the vsanName that matches VSAN ID 3 (vsanIndex is 3), then you would issue an SNMP get for vsanName.3.

SYNTAX Clause

The SYNTAX clause describes the format of the information, or value, that is returned when you monitor or set information in a MIB.

The Cisco NX-OS MIBs are defined with the SNMPv2 Structure of Management Information version 2 (SNMPv2-SMI) defined in RFC 1902. Some examples of SNMPv2-SMI syntax are as follows:

•Counter32—A nonnegative integer that increases until it reaches some maximum value. After reaching the maximum value, it rolls over to zero. For example, the variable ifInOctets, with a Counter32 syntax, counts the number of input octets on an interface.

•Gauge32—A nonnegative integer that increases until it reaches some maximum value. After reaching the maximum value, it stays fixed (no rollover).

•Counter64—A nonnegative 64-bit integer that increases until it reaches some maximum value. After reaching the maximum value, 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—An integer from -232 to 232-1.

•IPAddress—An 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—A 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.

MAX-ACCESS Clause

The MAX-ACCESS clause identifies the maximum access level for the associated MIB object. This clause can represent one of the following five states: read-create, read-write, read-only, accessible-for-notify, and not-accessible.

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

•read-write—You can read or modify this object.

•read-only—You can only read this object.

•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—You cannot read or write to this object. Table indices are typically objects that are not accessible.

AGENT-CAPABILITIES

In SNMP, capabilities files provide implementation details for the associated MIB. These files, called AGENT-CAPABILITIES, list supported conformance groups and any deviations from the MIB as implemented in the associated 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 Capabilities files may have implementation details for more than one software release. You need to match your software release to the corresponding AGENT-CAPABILITIES clause in this file.

---

Information About Cisco MIB Files

Cisco MIB files are a set of objects that are private extensions to the IETF standard MIB II. MIB II is documented in RFC 1213, Management Information Base for Network Management of TCP/IP-based Internets: MIB-II. Portions of MIB-II have been updated since RFC 1213. See the IETF website for the latest updates to this MIB:

http://www.ietf.org

If your NMS cannot get requested information from a managed device, such as a Cisco switch, the MIB that allows that specific data collection might be missing. Typically, if an NMS cannot retrieve a particular MIB variable, either the NMS does not recognize the MIB variable, or the agent does not support the MIB variable. If the NMS does not recognize a specified MIB variable, you might need to load the MIB into the NMS, usually with a MIB compiler. For example, you might need to load the Cisco private MIB or the supported RFC MIB into the NMS to execute a specified data collection. If the agent does not support a specified MIB variable, you must find out what version of system software that 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 Cisco NX-OS.

---

Cisco MIB File Directories

You can find Cisco MIBs at the following URL:

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

Cisco MIB files are organized into two directories: SNMPv1-SMI MIBs are in the SNMPv1 directory and SNMPv2-SMI MIBs are in the SNMPv2 directory. Cisco also includes supported IETF-standard MIBs at this website. Use this support list to access and download the individual MIB files.

MIB Loading Order

Many MIBs use definitions that are defined in other MIBs. These definitions are listed in the IMPORTS section near the top of the MIB.

For example, if MIB B imports a definition from MIB A, some MIB compilers require you to load MIB A prior to loading MIB B. If you get the MIB loading order wrong, you might get an error message about what was imported, claiming it is undefined or not listed in IMPORTS. If you receive an error, look at the loading order of the MIB definitions from the IMPORTS of the MIB. Make sure that you have loaded all the preceding MIBs first.

Here is a list of MIBs from which many other MIBs import definitions. The MIBs are 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

If you load the MIBs in this order, you can eliminate most of your load-order definition problems. You can load most other MIBs (those not listed here) in any order.

Accessing and Downloading Cisco MIB Files

You can access the Cisco MIB files in either of the following ways:

•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 located at the following site: http://tools.cisco.com/Support/SNMP/do/BrowseMIB.do?local=en. You can use this tool to translate SNMP object identifiers (OIDs) into object names, search object names, descriptions, browse OID trees, and download MIB files.

---

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

To access MIB files using your web browser, follow these steps:

---

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 Cisco NX-OS MIB support list.

---

If you are using Internet Explorer, you might need to enable passive FTP. To enable passive FTP, follow these steps:

---

Step 1 Open Internet Explorer, and click 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

To access MIB files using passive FTP, you must know the names of the MIB files that you want to download. See the "Using HTTP to Access and Download the MIB Files from Cisco.com" section to access the Cisco NX-OS support list for the names of supported MIBs. These steps assume that your passive FTP utility has UNIX-like commands.

To download MIB files with passive FTP, follow these steps:

---

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.

---

Understanding the 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 1-2 lists the Cisco MIB extensions that are linked to the ENTITY-MIB by entPhysical Index.

Table 1-2 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.
CISCO-ENTITY-SENSOR-MIB	Provides sensor data for environmental monitors such as temperature gauges.
CISCO-IMAGE-UPGRADE-MIB	Provides module image management based on entPhysicalIndex.
CISCO-ENTITY-VENDORTYPE-OID-MIB	Provides OID assignments for Cisco components for use by the ENTITY-MIB.

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 1-3.

Table 1-3 Varbinds Added to IF-MIB Notifications

Notification	Varbinds Added
linkUp	ifDescr
linkDown	ifDescr

See the Cisco Nexus 7000 Series System Management Configuration Guide, Release 5.x for details about enabling link notifications that use these additional varbinds.

Related Documentation

Cisco NX-OS includes the following documents:

Release Notes

Cisco Nexus 7000 Series NX-OS Release Notes, Release 6.x

NX-OS Configuration Guides

Cisco Nexus 2000 Series Fabric Extender Software Configuration Guide

Cisco Nexus 7000 Series NX-OS Configuration Examples

Cisco Nexus 7000 Series NX-OS FabricPath Configuration Guide

Configuring Feature Set for FabricPath

Cisco Nexus 7000 Series NX-OS Fundamentals Configuration Guide

Cisco Nexus 7000 Series NX-OS High Availability and Redundancy Guide

Cisco Nexus 7000 Series NX-OS Interfaces Configuration Guide

Cisco Nexus 7000 Series NX-OS IP SLAs Configuration Guide

Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration Guide

Cisco Nexus 7000 Series NX-OS LISP Configuration Guide

Cisco Nexus 7000 Series NX-OS MPLS Configuration Guide

Cisco Nexus 7000 Series NX-OS Multicast Routing Configuration Guide

Cisco Nexus 7000 Series NX-OS OTV Configuration Guide

Cisco Nexus 7000 Series OTV Quick Start Guide

Cisco Nexus 7000 Series NX-OS Quality of Service Configuration Guide

Cisco Nexus 7000 Series NX-OS SAN Switching Configuration Guide

Cisco Nexus 7000 Series NX-OS Security Configuration Guide

Cisco Nexus 7000 Series NX-OS System Management Configuration Guide

Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide

Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide

Cisco Nexus 7000 Series NX-OS Getting Started with Virtual Device Contexts

Cisco NX-OS FCoE Configuration Guide for Cisco Nexus 7000 and Cisco MDS 9500

NX-OS Command References

Cisco Nexus 7000 Series NX-OS Command Reference Master Index

Cisco Nexus 7000 Series NX-OS FabricPath Command Reference

Cisco Nexus 7000 Series NX-OS Fundamentals Command Reference

Cisco Nexus 7000 Series NX-OS High Availability Command Reference

Cisco Nexus 7000 Series NX-OS Interfaces Command Reference

Cisco Nexus 7000 Series NX-OS IP SLAs Command Reference

Cisco Nexus 7000 Series NX-OS Layer 2 Switching Command Reference

Cisco Nexus 7000 Series NX-OS LISP Command Reference

Cisco Nexus 7000 Series NX-OS MPLS Command Reference

Cisco Nexus 7000 Series NX-OS Multicast Routing Command Reference

Cisco Nexus 7000 Series NX-OS OTV Command Reference

Cisco Nexus 7000 Series NX-OS Quality of Service Command Reference

Cisco Nexus 7000 Series NX-OS SAN Switching Command Reference

Cisco Nexus 7000 Series NX-OS Security Command Reference

Cisco Nexus 7000 Series NX-OS System Management Command Reference

Cisco Nexus 7000 Series NX-OS Unicast Routing Command Reference

Cisco Nexus 7000 Series NX-OS Virtual Device Context Command Reference

Cisco NX-OS FCoE Command Reference for Cisco Nexus 7000 and Cisco MDS 9500

Other Software Documents

Cisco NX-OS Licensing Guide

Cisco Nexus 7000 Series NX-OS MIB Quick Reference

Cisco Nexus 7000 Series NX-OS Software Upgrade and Downgrade Guide

Cisco NX-OS System Messages Reference

Cisco Nexus 7000 Series NX-OS Troubleshooting Guide

Cisco NX-OS XML Interface User Guide

Documentation Feedback

To provide technical feedback on this document, or to report an error or omission, please send your comments to nexus7k-docfeedback@cisco.com. We appreciate your feedback.

Obtaining Documentation and Submitting a Service Request

For information on 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, at:

http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html

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 or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: 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. (1110R)

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.

© 2013 Cisco Systems, Inc. All rights reserved.