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1
Introduction to Network Management
chap 1: NMS 2
Objective of this chapterIntroduction to Network Management Presents a brief overview of network management.
Network Management Architectures Provides a brief overview of the common components
of network management architectures. components of network management system (NMS)
Open System Interconnection (OSI) Network Management Model Introduces the ISO OSI network management model.
Definition
Definition
Network Management?
chap 1: NMS 6
Function of Network ManagementDesigned to simplify the operation of large internetworks. This includes:
control corporate strategic assets from a central position aids in strategically planning for network growth. ? operate independently of the system it monitors support multiple protocols operate as transparently as possible improve services - maintaining network stability, tuning network
performance, balance various needs, including applications, systems and
technologies troubleshooting problems that might arise. ? ?
chap 1: NMS 7
ChallengesAutomated processes Repetitive tasks can be performed reliably
and predictably by automated processes. Integration across diverse network environments (heterogeneous networks) Management capabilities can be made
available in geographically dispersed environments or in networks using multiple protocols or platforms.
chap 1: NMS 8
Challenges (2)? Constant monitoring alerts network
administrators to problems quickly. ? Tracking past problems makes
finding solutions easier, while recording values for performance, availability, and other areas can uncover trends that might affect future growth.
chap 1: NMS 9
Network Management System (NMS)A typical model of network management systems consists of ?-- the central controller ?-- network devices like routers and
gateways which interconnect sub-networks
a protocol for communications, such as SNMP, between network devices and the controller, and
a set of parameters to be monitored and controlled
chap 1: NMS 10
Components of NMSNetwork management stationManaged Device
agent management
database
?
chap 1: NMS 11
Network Management StationThe NM station is a computer system that contains software processes known as management entities.
? should be installed with a
network management platform (protocol) such as HP OpenView, SUN SuNet Manager, IBM NetView.
normally, network management application tools are also required, such as CiscoWorks
HP OpenView for Windows network management platform
HP OpenView for Windows network management platform
Health Monitor
Health Monitor
Configuration Builder
Configuration Builder
ShowCommands
ShowCommands
Windows with WINSOCK compliant TCP/IP stackWindows with WINSOCK compliant TCP/IP stack
CiscoViewCiscoView
CiscoWorks for Windows
Network Management Network Management Platform and ApplicationsPlatform and Applications
chap 1: NMS 12
Network Management Station (2)Management entities poll agents in managed devices (automatically or by user request) to check the values of certain variables.
Management entities also react to alerts from managed devices by executing one or more actions, such as notifying the network administrator, performing event logging,
shutting down a system, or attempting system repairs.
NetworkManagementProtocols Network
Devices
ManagementStation
request
replies, trap read
writeMIB
chap 1: NMS 13
Network Management Interactions?
network management station NMS queries each network devices ND periodically, so, consumes more bandwidth.
NMS sends ‘request’ message to NDs to get status information or set operation parameters (MIB variables)
network devices return ‘reply’ message carrying status information (MIB variables)
? Traps -- network devices generate warning
messages when a critical threshold is reached
NMS log/record alarm messages and alert the network engineers
event-triggered, so, consumes little bandwidth
request
trap
replies MIB
MIB
chap 1: NMS 14
Managed DevicesManaged devices Managed devices are systems that fall
under the control of an NMS. Managed devices contain software modules
called agents. Agents compile and store information about
the managed device in a management database and provide this information (proactively or reactively) to the NMS.
Agents define the parameters that an NMS can monitor or configure
chap 1: NMS 15
Common NM Protocols Simple Network Management Protocol (SNMP)
SNMP is a protocol that facilitates exchange of management information between network devices, primarily in TCP/IP environments.
In 1988, the Internet Activities Board IAB committee proposed the SNMP as the short-term solution for network management.
Since then, the simple structure and good performance of SNMP has make it popular around the world. It is likely that SNMP will be a long-term solution.
Remote Monitor (RMON) RMON is a standard monitoring specification for exchanging
network monitoring data.
Common Management Information Protocol (CMIP) An OSI network management protocol created and standardized by
ISO for the monitoring and control of heterogeneous network.
16
Network Management Architecture
chap 1: NMS 17
NM Architectures & modelMost network management architectures are implemented using similar structures and sets of relationships.Three network management architecture
Centralized Distributed Hierarchical
Regardless the NM architecture, there are two basic components in a typical network management environment:
Managed devices a network host with an agent
Network Management System (NMS) for example: HP OpenView
chap 1: NMS 18
Centralized Architectureall queries are sent to a single management system applications are installed on the
central NMS responds to trap messages sent from
managed nodes strength
? ideal for small to medium-size networks
weakness NMS can easily be overburdened NMS may be bombarded by numerous
traps send from managed nodes MIBMIBMIB
NMS
AgentAgent Agent
chap 1: NMS 19
Distributed Architectureat least two peer NMSdistributed architecture is usually for networks in different places (geographically)strength
not be overburnded suitable for medium to large-sized networks ? provide fault-tolerant NMS can poll managed nodes on other areas
MIBMIBMIB
NMS
Agent Agent
MIBMIBMIB
NMS
Agent Agent
chap 1: NMS 20
Hierarchical Architecturecombine a centralized system with a distributed systemmost complex architecturesuitable for large and complex network configurationStrength
?
MIBMIBMIB
NMS
Agent Agent
MIBMIBMIB
NMS
Agent Agent
Centralized NMS
21
ISO-OSI Network Management Model
also known as FCAPS model
chap 1: NMS 22
Open System Interconnection (OSI) NM Model The Open System Interconnection (OSI) network management model provides a broad framework for network management implementations. The model is specified by the International Organization for Standardization (ISO)
Security
Fault Performance
Configuration
Accounting
chap 1: NMS 23
OSI NM ModelThe OSI network management model divides network management into five key areas:Also known as FCAPS model fault, configure, account, performance & security
Fault management Fault management manages network problems in
order to keep the network running effectively.
Configuration management Configuration management monitors network and
system configuration information.
chap 1: NMS 24
OSI NM Model (2)Accounting management Accounting management measures and
regulates network utilization.
? Performance management maintains
internetwork performance at acceptable levels.
Security management Security management controls access to
network resources.
chap 1: NMS 25
Fault Management Manages network problems to keep the network running reliably and efficiently.Fault management process involves the following steps
1. Detecting the problem symptoms. 2. Isolating the problem. 3. Fixing the problem automatically (if possible) or
manually. 4. Testing the fix on all important subsystems. 5. Logging the detection and resolution of the
problem.
chap 1: NMS 26
Fault Management (2)Test all major sub-system and record the result for future referenceCommon display messages in networking devices Green: ? Yellow: May have problems Red: in a state of error and is no longer in service Blue: is running but has experience an error Orange: configuration error Gray: no information about the device is available Purple: device is being queried or polled
chap 1: NMS 27
Configuration ManagementConfiguration Management monitors network and system configuration information and stores it in a configuration management database. The maintenance of this database allows network administrators to track hardware, software, and other network resources
chap 1: NMS 28
Configuration Management (2)Each network device has a variety of information associated with it: Software version information for the operating
system, protocol software, or management software.
Hardware version information for the interfaces or hardware controllers.
Contact information indicating who to contact if problems with the device arise.
Location information indicating the physical location of the device.
chap 1: NMS 29
Configuration Management (3)CM Information Associated with a Managed Device
chap 1: NMS 30
Accounting Management Measures network ? parameters in order to regulate individual and group uses of the network. Minimizes network problems and maximizes fairness of user access to the network because network resources can be portioned based on network capacity and user needs.
chap 1: NMS 31
Account Management (2)
There are 4 Steps in Account Management:
1. Measuring the use of all important network resources.
2. Analyzing the results to determine the current usage patterns.
3. Setting usage quotas. 4. Measuring resource utilization on an
ongoing basis.
chap 1: NMS 32
Performance Management Maintains internetwork performance at acceptable levels by measuring and managing various network performance variables. Performance variables include network ?, user response times, line utilization, and others.Performance management involves three basic steps:
1. Gathering data relating to key performance variables. 2. Analyzing data to determine the normal (baseline)
performance levels. 3. Determining appropriate performance thresholds for
each variable so that exceeding these thresholds indicates a network problem worthy of attention.
chap 1: NMS 33
Performance Management (2)
100
80
60
40
20
10Last 3.000 Average 16.154 Minimum
63.000Maximum2.000
Duration 1:40
Color Scale Counter Instance Parent Object Computer
1.0001.0001.0001.0001.000
- - -- - -- - -- - -- - -
\\LONDON\\LONDON\\LONDON\\LONDON\\LONDON
ProcessorProcessPhysicalDiskMemoryFTP Service
% Processor Time% Processor Time% Disk TimePage/secBytes Received/sec
_Totalexplorer0 C: D:- - -Default FTP Site
PerformanceConsole Window Help
Action View Favorites
Tree Favorites
Console RootSystem MonitorPerformance Logs and Alerts
chap 1: NMS 34
Performance Management (3)? when performance becomes unacceptable
(that is, a user-defined threshold is exceeded), the managed device reacts by sending an alert to the network management system (NMS).
Proactive simulation is used to project how network
growth will affect performance metrics. These simulations alert administrators to impending problems before they affect network users.
chap 1: NMS 35
Performance Management (4)
Reactive PM Components1. The management entity continually monitors
performance variables in managed devices. 2. When a particular performance threshold is
exceeded, the NMS or the managed device detects the problem.
3. If the managed device detects the problem, it generates an alert and sends it to the NMS.
4. The NMS takes an appropriate action, such as alerting the network administrator.
chap 1: NMS 36
Windows Task ManagerWindows Task Manager
File Options View Windows Help
Applications Processes Performance
Task StatusBuilding Schematic - Paint
Memo to Supervisor - WordPad
Calculator
My Computer
Running
Running
Running
Running
End TaskEnd Task Switch ToSwitch To New Task...
Processes: 30 CPU Usage: 2% Mem Usage: 103500K / 310892K
Windows Task ManagerFile Options View Help
Processes: 30 CPU Usage: 6% Mem Usage: 103452K / 310892K
Applications Processes Performance
Image Name PID CPU CPU Time Mem Usage
System Idle ProcessSystemsmss.execsrss.exewinlogon.exeservices.exelsass .exesvchost .exespoolsv .exemspaint .exemsdtc .exeinojobsv .exedfssvc .exesvchost .exeismserv .exellssrv .exentfrs.exeregsvc.exe
08
168196220148160472492624704808824840864880928968
960000000000000000000200000000000000
4:52:370:00:270:00:000:00:200:00:090:00:140:00:320:00:000:00:000:00:040:00:000:07:460:00:000:00:000:00:000:00:010:00:090:00:00
16 K212 K344 K
1,820 K4,408 K8,228 K
15,768 K2,648 K4,184 K
352 K3,428 K5,704 K2,336 K3,416 K5,348 K3,860 K1,108 K
844 K
Show processes from all users End Process
Windows Task ManagerFile Options View Help
Applications ProcessesPerformance
Processes: 30 CPU Usage: 3% Mem Usage: 101600K / 310892K
CPU Usage
MEM Usage
CPU Usage History
Memory Usage History
Totals
Commit Charge (K)
Physical Memory (K)
Kernel Memory (K)
3%
10 1600K
HandlesThreadsProcesses
TotalLimitPeak
TotalAvailableSystem Cache
TotalPagedNonpaged
5932381
30
1306122774050704
101600310892116896
2280415704
7100
chap 1: NMS 37
Security Managementcontrols access to network resources, and prevents network sabotage (intentional or unintentional) and unauthorized access to sensitive information. aids administrators in creating a secure network environment. This includes: partitioning network resources into authorized
and unauthorized areas, mapping groups of users to those areas, and monitoring, policing, and logging user access to
resources in those areas.
chap 1: NMS 38
SummaryObjective and challenge of Network managementNetwork management Archiectures: centralized, distributed, hierarchicalComponents: NM Station, Managed device, protocolISO-OSI model: FCAPS fault configuration account performance security