1 Introduction to Network Management

chap 1: NMS2 Objective of this chapter Introduction 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

Network Management?

chap 1: NMS6 Function of Network Management Designed 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: NMS7 Challenges Automated 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: NMS8 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: NMS9 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: NMS10 Components of NMS Network management station Managed Device agent management database ?

chap 1: NMS11 Network Management Station The 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 Show Commands Show Commands Windows with WINSOCK compliant TCP/IP stack CiscoView CiscoWorks for Windows Network Management Platform and Applications

chap 1: NMS12 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. Network Management Protocols Network Devices Management Station request replies, trap read write MIB

chap 1: NMS13 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

chap 1: NMS14 Managed Devices Managed 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: NMS15 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: NMS17 NM Architectures & model Most 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: NMS18 Centralized Architecture all 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 MIB NMS Agent

chap 1: NMS19 Distributed Architecture at least two peer NMS distributed 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 MIB NMS Agent MIB NMS Agent

chap 1: NMS20 Hierarchical Architecture combine a centralized system with a distributed system most complex architecture suitable for large and complex network configuration Strength ? MIB NMS Agent MIB NMS Agent Centralized NMS

21 ISO-OSI Network Management Model also known as FCAPS model

chap 1: NMS22 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: NMS23 OSI NM Model The 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: NMS24 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: NMS25 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: NMS26 Fault Management (2) Test all major sub-system and record the result for future reference Common 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: NMS27 Configuration Management Configuration 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: NMS28 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: NMS29 Configuration Management (3) CM Information Associated with a Managed Device

chap 1: NMS30 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: NMS31 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: NMS32 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: NMS33 Performance Management (2) Last3.000Average Minimum Maximum Duration1:40 ColorScaleCounterInstanceParentObjectComputer \\LONDON Processor Process PhysicalDisk Memory FTP Service % Processor Time % Disk Time Page/sec Bytes Received/sec _Total explorer 0 C: D: Default FTP Site Performance ConsoleWindowHelp Action View Favorites TreeFavorites Console Root System Monitor Performance Logs and Alerts

chap 1: NMS34 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: NMS35 Performance Management (4) u Reactive PM Components 1. 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: NMS36 Windows Task Manager File Options View Windows Help ApplicationsProcessesPerformance TaskStatus Building Schematic - Paint Memo to Supervisor - WordPad Calculator My Computer Running End Task Switch To New Task... Processes: 30 CPU Usage: 2%Mem Usage: K / K Windows Task Manager File Options View Help Processes: 30 CPU Usage: 6% Mem Usage: K / K ApplicationsProcessesPerformance Image NamePID CPUCPU TimeMem Usage System Idle Process System smss.exe csrss.exe winlogon.exe services.exe lsass.exe svchost.exe spoolsv.exe mspaint.exe msdtc.exe inojobsv.exe dfssvc.exe svchost.exe ismserv.exe llssrv.exe ntfrs.exe regsvc.exe :52:37 0:00:27 0:00:00 0:00:20 0:00:09 0:00:14 0:00:32 0:00:00 0:00:04 0:00:00 0:07:46 0:00:00 0:00:01 0:00:09 0:00:00 16 K 212 K 344 K 1,820 K 4,408 K 8,228 K 15,768 K 2,648 K 4,184 K 352 K 3,428 K 5,704 K 2,336 K 3,416 K 5,348 K 3,860 K 1,108 K 844 K Show processes from all users End Process Windows Task Manager File Options View Help ApplicationsProcessesPerformance Processes: 30CPU Usage: 3%Mem Usage: K / K CPU Usage MEM Usage CPU Usage History Memory Usage History Totals Commit Charge (K) Physical Memory (K ) Kernel Memory (K ) 3% K Handles Threads Processes Total Limit Peak Total Available System Cache Total Paged Nonpaged

chap 1: NMS37 Security Management controls 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,areas mapping groups of users to those areas, and monitoring, policing, and logging user access to resources in those areas.

chap 1: NMS38 Summary Objective and challenge of Network management Network management Archiectures: centralized, distributed, hierarchical Components: NM Station, Managed device, protocol ISO-OSI model: FCAPS fault configuration account performance security