SNMP Applications

1
SNMP Applications
2
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

3
Introduction

• Simple Network Management Protocol (SNMP)
• Allows broadcasters to monitor multiple vendors
  equipment using simple commands using UDP IP
  protocol
• UDP (User Datagram Protocol)
• does not confirm data arrives at destination like
  TCP
• SNMP is not designed for controlling equipment

4
Introduction

• SNMP can monitor
• Accounting Management
• Tracks use and assigns charges for use of
  resources.
• Configuration Management
• Controls, identifies and collects data from
  resources.
• Performance Management
• Evaluates performance of resources.
• Security Management
• Protects resources and logs access attempts.
• Event/Fault Management
• Event detection
• Fault detection and correction

5
Introduction

• Classroom Setup
• NuDesign SNMP management software that you should
  already have on your computer
• Standalone classroom network consisting of
• Your computers
• NuDesign SNMP manager software makes your
  computer an SNMP manager
• Need to configure your computer for an assigned
  IP address
• WFM/WVR7120 one for each team
• SNMP Agent
• TG700 one for each team
• Not an SNMP agent, will use as signal source for
  WFM/WVR7120
• MTM400A for class use
• SNMP Agent
• SPG600 for class use
• SNMP Agent
• Process
• Will discuss individual section of class and do
  related hands-on training

6
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

7
SNMP Overview

• Network Management Station (Manager)
• NuDesign software on your computer
• Network Managed Agent (Agent)
• Part of WFM/WVR (except 4K/5K), AMM, MTM, MTS,
  SPG, MTX, RTX
• Collects and locally stores information on
  agents operation
• Report the information to the manager
• Change its parameters as directed by the manager

IP Router (Agent)
NME
App
OS
WFR7120 (Agent)
NMA - Network Management ApplicationNME -
Network Management EntityApp - Application
(Network Resource) OS - Operating System
NME
App
OS
8
SNMP Overview

• Agent Managed Objects
• Network resources (agents) have managed objects
  
• Agent Management Information Base (MIB)
• The managed objects are described in a file
  called the Management Information Base

WFM7120(Agent)
App
NME
Managed Objects- vecVarGain- vecCenter-
arrTable- arrEntry- arrMode- arrFmt- etc...
Manager
NMA
MIB
NME
App
OS
OS
9
SNMP Overview

• SNMP MIB Object Identifiers (OID)
• Dotted Decimal Notation
• ISO, ORG, DOD, Internet
• MIB Browsers
• VTS uses NuDesign
• Cambridge uses
• MG-SOFT
• HPOpenView
• This lab will also use ACE-COMM
• Many more available!
• ASN.1 (Abstract Syntax Notation.1)
• Standard for formatting information
• http//asn1.elibel.tm.fr/introduction/index.htm
• View MIB OIDs (Object Identifiers)Using NuDesign
• NuDesign ViewgtASN.1

1.3.6.1 path designator to this point
10
SNMP Overview

• MIB Format Defined by ASN.1 sysDescr
  OBJECT-TYPE SYNTAX DisplayString (Size
  (0..255)) ACCESS read-only STATUS
  mandatory DESCRIPTION "A
  textual description of the entity. This value
  should include the full name and
  version identification of the
  system's hardware type, software
  operating-system, and networking
  printable ASCII characters. system 1
  
• Syntax
• DisplayString
• Integer
• TimeTicks
• Many more plus user defined!
• Access
• read-only
• read-write
• not-accessible
• write-only (Really! One is in the MTM400A)

11
SNMP Overview

• SNMP Common MIB Objects
• RFC1213 defines common OIDs that may apply to
  most SNMP devices
• 1.3.6.1.2.1 dotted decimal notation to this point
• View examples and System using NuDesign
• Notice dotted decimal notation in lower left
  corner of NuDesign and ASN.1 window

12
SNMP Overview

• SNMP Enterprise Defined MIB Objects
• Companies/Agencies assigned unique designation
• Tektronix is 128
• All Tektronix VPL unique SNMP OIDs starts with
  dotted decimal notation 1.3.6.1.4.1.128.5
• Will see in follow steps
• Show enterprise number list

13
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

14
Finding SNMP Devices

• To manage SNMP devices, need to discover them.
• Need to manage list of discovered SNMP devices so
• Remove expired devices
• Add new devices
• To do this using the NuDesign MIB Browser,
  perform the steps in SNMP Applications Lab, tasks
  1 and 2.

15
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

16
Get/Set/Walk Commands

• SNMP Simple because of limited command set,
  Get/Set/Trap
• To get or set OID, need community password
• default Read password public
• default Write password private
• can change passwords
• SNMPv1 v2C same level of security
• SNMPv3 has encrypted password capability

17
Get/Set/Walk Commands

• Get
• manager requests data from agent OID
• OID does not exist, no read access or wrong
  password timeout error

18
Get/Set/Walk Commands

• Walk
• Walk is series of Get requests
• manager requests OID data starting at selected
  MIB OID

19
Get/Set/Walk Commands

• Set
• manager attempts to set agent OID
• OID does not exist, no set access or wrong
  password timeout error
• some agents do not allow set due to poor
  security

20
Get/Set/Walk Commands

• To manage SNMP devices, need to discover them.
• Need to manage list of discovered SNMP devices so
• Remove expired devices
• Add new devices
• To do this using the NuDesign MIB Browser,
  perform the steps in SNMP Applications Lab, task
  3.

21
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

22
Walk OID Without Tek MIB

• SNMP MIB Structure
• MIB 2 defined by RFC1213 which is loaded into
  NuDesign
• Defines MIB II OIDs so NuDesign can make OIDs
  human readable
• Without the MIB, NuDesign does not know how to
  interpret OIDs
• The same thing is true for the Tektronix SNMP
  devices
• Need to load Tektronix MIB to interpret Tektronix
  OIDs
• Will do in next sections
• For now Tektronix MIBs should be unloaded

23
Walk OID Without Tek MIB

• SNMP MIB Structure
• View RFC1213

24
Walk OID Without Tek MIB

• Walking WFM/WVR without Tek MIB loaded
• Just get OID values with no interpretation
• Tek OID is 128
• TVT OID is 5

25
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

26
Describe Tek MIBS and Load Them

• Tektronix MIBs
• AD-MPEG-MIB
• MPEG related OIDs
• AD-SYSTEM-MIB
• System related OIDs
• SPG300-600-MIB
• For SPG series
• WFM-MIB
• For WVR/WFM/AMM
• WVR7100-MIB
• old MIB for WVR
• replaced by WFM-MIB
• All on class CD-ROM

27
Describe Tek MIBS and Load Them

• Tektronix Documents
• 077-0078-00 WFM/WVR/AMM MIB Reference
• Describes OID/Instrument assignments
• Page 2
• WFM-MIB
• Describes OID details using ASN.1 format
• All on class CD-ROM

28
Describe Tek MIBS and Load Them

• Tektronix Documents
• 071-2498-00MTM400A MPEG TS MonitorProgrammer
  Manual

• Tektronix Documents
• 071-2498-00MTM400A MPEG TS MonitorProgrammer
  Manual
• AD-SYSTEM-MIB
• non-application specific system information
• AD-MPEG-MIB
• MPEG related information including I/F, events,
  PIDs, tables and MPEG structure tables
• All on class CD-ROM

29
Describe Tek MIBS and Load Them

• Loading MIB into NuDesign
• MIB Location
• Load MIB
• Designate MIBs

30
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

31
Walk OIDs with Tek MIB

• Walk Currently Selected SNMP Agent
• WFM/WVR7120 selected
• If walk SPG600-300 MIB, will not return values

32
Walk OIDs with Tek MIB

• Walk Currently Selected SNMP Agent
• Walk WFM/WVR7120 to see details of the selected
  agent MIB
• To do this using the NuDesign MIB Browser,
  perform the steps in SNMP Applications Lab, task
  4.

33
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

34
MIB Tables

• Have discussed single value OIDs so far
• Need two dimensional tables to allow for multiple
  instances of the same OIDs
• Tables created by Sequence of OID type
• Example table is WFM/WVR vecTable

35
MIB Tables

• WFM/WVR vecTable
• each WFM/WVR display tile can display vectorscope
• each vectorscope display can have different
  settings
• see MIB listing for vector parameters
• need table to store each tiles vectorscope
  settings

36
MIB Tables

• WFM/WVR Vector Table
• vecTable Sequence of OID is 1.3.6.1.4.1.128.5.2.
  10.6.2
• vecTable four rows
• vecTable row vecMode, vecHorPos, vecVertPos,
  vecTargets, vecGain, vecVarGainEnable,
  vecVarGain, vecCenter
• Set WFM/WVR tile to Vector
• Access vecTable data
• Make changes and reacquire vecTable
• To do this using the NuDesign MIB Browser,
  perform the steps in SNMP Applications Lab, task
  5.

37
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

38
Chart OID Values

• Polls user selected OID/table at fixed intervals
• Display returned values on chart
• Chart based on changes over time or absolute
  value
• Can only chart integer OIDs!
• why only 5 of 8 vecTable OIDs shown
• Alarm triggers basedon defined conditions
• To do this using the NuDesign MIB Browser,
  perform the steps in SNMP Applications Lab, task
  6.

39
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

40
Log OID Values

• Charting limited to numeric OIDs
• Can log all OID types
• Logging polls user selected OID/table at fixed
  intervals
• Save values as .txt file
• To do this using the NuDesign MIB Browser,
  perform the steps in SNMP Applications Lab,
  task 7.

41
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

42
Using Excel Spreadsheets

• OID Log data can be displayed graphically using
  an Excel spreadsheet
• Import the data into Excel
• use the Excel chart wizard to graph data
• Create chart using Excel, as described in SNMP
  Applications Lab, task 8.

43
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

44
Trap on OID Values

• Polling Vs. Trap
• Poll manager requests agent data with Get
  request
• Trap agent generates report that is not the
  result of a Get request
• Trap can reduce or increase network traffic
  compared to poll
• MTM400A has special OID to reduce Trap traffic

Event ReportHere isdata.
45
Trap on OID Values

• Manager needs SNMP tool that can capture traps
• Agent (WFM/WVR) needs to be set up
• SNMP Enable On
• SNMP Trap Enable On
• SNMP Trap Address Managers IP Address
• Alarms on and set to generate SNMP message
• Trap WFM/WVR OIDs, as described in SNMP
  Applications Lab, task 9.

46
Objectives

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A

47
SNMP and the MTM400A

• Set/Get Trap Server Address
• Get/Set Trap Server Time Out
• Change/Delete Trap Server Address
• Record/Decode Traps

48
SNMP and the MTM400A

• Set/Get Trap Server Address
• SNMP managers subscribe to MTM400A with Set to
  write-only OID to get traps
• To see list of subscribed SNMP managers getting
  trap messages, need to Get this table

49
SNMP and the MTM400A

• Set/Get Trap Server Address
• MTM400A read/write passwords both set to public
• Default settings are read is public, write is
  private
• To use Set command in MTM400A, must use public
• Will examine in lab

50
SNMP and the MTM400A

• Get/Set Trap Server Time Out
• WFM/WVR7120 trap address stay till
  changed/deleted by user
• MTM400A Trap addresses deleted after number of
  user define number of minutes
• Prevents buildup of SNMP manager addresses
• Get/Set trap server time out here
• Managers have to re-subscribe to the MTM400A on a
  regular basis
• If trapSinkTimeOut set to 0, server address
  does not time out
• Different time outs can be set for different
  managers

51
SNMP and the MTM400A

• Get/Set Trap Server Time Out
• Can Set (write)/Get (read) time out minutes

52
SNMP and the MTM400A

• Change/Delete Trap Server Address
• Can delete trap server addresses
• Addresses auto delete on time out
• Unless time out set to 0 for that address
• Can write new ones at any time

53
SNMP and the MTM400A

• Record/Decode Traps
• trapThrottle OID
• controls trap rate to prevent network congestion
• Sets total number of traps per minute
• 100 trap buffer that can overflow and loose traps

54
SNMP and the MTM400A

• Record/Decode Traps
• MTM400A
• Select MTM400A parameters that will generate
  traps
• Right click on item and select desired trap
  action
• SNMP Manager
• Run trap capture software like NP_TRAP

55
Summary

• Introduction
• SNMP Overview
• Finding SNMP Devices
• Get/Set/Walk Commands
• Walk OIDs without Tek MIB
• Describe Tek MIBs and Load Them
• Walk OIDs with Tek MIB
• MIB Tables
• Chart OID Values
• Log OID Values
• Using Excel Spreadsheets
• Trap on OID Values
• SNMP and the MTM400A