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Transcript of On the Job with a Network Manager. Activities performed by network managers Tools used by network...
Chapter 2
On the Job with a Network Manager
Activities performed by network managers Tools used by network managers How management tools and management
technology are used to achieve a given purpose
Support for network personnel The organization of tasks and workflows How network management personnel work
together Procedures that management personnel must
follow to complete a job
Overview - Topics
After reading this chapter you should gain a better understanding of the following: The types of operational tasks network
personnel face on a day-to-day basis How network management technology
supports network operators The different types of management tools
that network personnel use to do their jobs
Objectives
The three different scenarios provide an overview of the role that a network manager plays within an organization
Responsibilities differ widely depending on the type and size of the organization
The examples are illustrative and by no means comprehensive
A Day in the Life of a Network Manager
Pat is a network operator at the Network Operations Center (NOC) of GSP
Her group is responsible for monitoring the global backbone network and the access network
GSP is a multibillion-dollar business that provides global services with “five nines” service availability
Any disruption to service would cause revenue losses in the millions of dollars, expose GSP to penalties and liability claims, and put jobs in jeopardy
Pat: An Operator for Global Service Providers
A Command Central inside an NOC
Pat works in command central Big screens map the main sites of the
network and show statistics on network utilization
Map items appear in green when everything is operational
Occasionally entire nodes on the map turned yellow or red when connectivity is affected
A smaller screen on Pat’s desk shows a list of trouble tickets, which are used to track and resolve current network problems
Screen Views
The trouble tickets have two sources◦ customer-reported problems and ◦ Network problems
Reps provide “tier 1 support” for customers
If a service rep cannot help a customer, the customer is transferred to a rep with more troubleshooting experience
Pat’s group provides the third tier of support
Trouble Ticket Support
Trouble tickets typically contain◦ a description of the problem◦ who is affected◦ contact information
Sometimes this information is missing or in error
Trouble Ticket Contents
The second source of tickets Reported by systems that monitor alarm
messages sent by network equipment The problem with alarm messages is that
they rarely indicate the root cause of the problem
In most cases, they reflect symptoms that could be caused by any number of things
Network Related Trouble Tickets
Pat doesn’t see every single alarm in the network The alarm monitoring system tries to group
messages that appear to point to the same underlying problem
Viewing grouped messages is much more practical than addressing individual alarms
In the past, Pat has seen 20 tickets all related to the same problem
GSP has recently made significant progress in reducing redundancy
Despite the progress made many tickets still relate to the same underlying cause
Trouble Ticket Aggregation
Pat must first acknowledge that she has read each ticket
If she does not acknowledge the ticket, it is automatically escalated to her supervisor
Next Pat analyzes the ticket information She uses a monitoring application for the affected
part of the network to see what is going on She starts by verifying the symptoms that are
reported in the network In some cases, Pat decides that a piece of
equipment needs to be replaced
Trouble Ticket Resolution
If equipment needs replacement Pat opens a work order system to create an order for a new part
It is not Pat’s responsibility to dispatch a field technician
Sometimes technicians are dispatched to a remote location to inspect and/or replace the equipment
In other cases the rack-mounted equipment in the NOC is affected
Work Order System
Rack-Mounted Network Equipment
Cabling and Patch Panels
When the technicians exchange a part, they use a bar-code scanner that automatically updates the central inventory system
Pat enters what she did and when resolution is expected on the trouble ticket
For now, she is finished When the work order is fulfilled a notification from
the system will be sent to her in-box Pat used to close the tickets before receiving
notification from the work order system She now understands that procedures are essential
for GSP to control quality of the services it provides
Work Order Fulfillment
Chris and a colleague are responsible for the computer and networking infrastructure of the RC Stores headquarters and 40 branch locations
RC Stores’ network contains almost 100 routers◦ Typically, an access router and a wireless router in
the branch locations and◦ additional networking infrastructure in the
headquarters and at the warehouse
Chris: Network Administrator for a Medium-Size Business
RC Stores Network
A managed service provider (MSP) is used to interconnect the various locations of its network◦ The MSP has set up VPN tunnels between the access routers at
each site that connects the branch locations to the headquarters◦ The entire network can be managed as a single network
Chris runs a management platform from a workstation at his desk◦ The application provides a graphical view of the network that
displays the network topology◦ Chris has built a topology map that groups multiple routers into
“clusters”◦ A typical management application screen is shown in the next
slide Management applications support some statistical views
as well
RC Network Overview
A Typical Management Application Screen
Cisco Packet Telephony Center
Management Application Screen with Performance Graphs
Cisco Works IP Performance Monitor
Chris adds a phone for a new user and troubleshoots a problem that he suspects might be caused by problems on MSP’s network
Chris handles multiple responsibilities because of the smaller size of his organization and network
An Example Administrator Task
Sandy works in the Internet Data Center for a global Fortune 500 company, F500, Inc.
The data center◦ is the center of the company’s intranet, extranet, and Internet
presence◦ hosts the company’s external website and connects customers to
the online ordering system◦ is host to all the company’s crucial business data ◦ hosts the company’s internal website which provides access to
the data given the proper access privileges Since the functions provided by the data center are crucial
to its business, F500, Inc. decided not to outsource them The way F500, Inc. organizes and manages its processes
and supply chains differentiates it from its competitors
Sandy: Administrator and Planner in an Internet Data Center
Sandy is to develop a plan to accommodate a new supplier
It will involve configuring ◦ server and storage infrastructure critical for the business
relationship as well as◦ an extranet over which the shared data can be accessed
Sandy has a list of the databases that need to be shared and backed up and storage and network capacity must be assessed
Sandy’s main concern is security Sandy needs to set up a new VLAN to separate traffic on
the extranet from other network traffic A typical networks configuration screen is shown in the
next slide
Developing a Plan for a Supplier
A Management Application Screen for Port Configuration
Access control lists (ACLs) on the routers need to be updated to reflect the new extranet security policy
Finally, authentication, authorization, and accounting (AAA) servers need to be configured
Sandy must determine where the data will be hosted and how her decision will impact the internal data center topology
Sandy uses a performance-analysis application to make these determinations
Data are stored in multiple places. This will be transparent to applications.
A common uniform resource identifier (URI) will be used to address the data
Additional Plan Concerns
Pat, Chris, and Sandy handle their jobs in different ways The differences depend upon the size and purpose of the network and the
network functions that individual manages. Chris manages numerous aspects of his network.
Different tools are used by the managers to carry out the required management tasks
Pat’s job is determined by guidelines, procedures, and the way the work is divided at her organization
Both manually-executed and automated tasks exist Management tasks required abstract concepts that had to be broken down
into numerous subtasks Running a network involves monitoring operations, diagnosing failures,
configuring services, analyzing historical data, planning, security, and workforce management
Integration affects operator productivity◦ Pat used integrated applications to manage trouble tickets◦ Chris had to repeat some work because of a lack of integration in his phone system
applications
Observations
Device managers and craft terminals Network and element analyzers Management Platforms Collectors and Probes Intrusion Detection Systems Performance Analysis Systems Alarm Management Systems Trouble Ticket Systems Work Order Systems Workflow Management Systems and Workflow Engines Inventory Systems Service Provisioning Systems Service Order-Management Systems Billing Systems
Typical Management Tools
Craft terminals provide a graphical view of the physical configuration of network equipment
Craft terminals are used to◦ log into a device◦ view its current status◦ change configuration settings◦ perform diagnostic self-tests and◦ downloading software images
Managed equipment may provide a “built-in” craft interface that renders a view of the device
Field technicians typically load craft terminal software onto their notebooks so they can connect to a device and managed it via a USB or serial interface
Craft Terminals/Device Managers
A Graphical Device View
CiscoView for Catalyst 6500
Network or packet analyzers are used to view and analyze network traffic for diagnostic and and troubleshoot purposes
Network analyzers◦ capture or “sniff” packets that traverse the ports
of a router or switch and◦ Display packets in a human-readable format that
an experienced network operator can interpret
Network Analyzers
Similar to craft terminals but◦ contain a database for retaining device configuration
information◦ receive event messages from devices on the network
and◦ discover equipment deployed on the network
Element Managers may have an interface that allows applications to manage equipment through the element manager. This provides ◦ data synchronization between apps◦ a simpler user interface and◦ reduced management load
Element Managers
General-purpose applications used to monitor and manage the network, comparable to element managers
May be proprietary Often include toolkits that extend the
management platform Often compared to a PC operating system
because it provides a means for communicating with network devices and tracking communications via an internal database
Management Platforms
Collectors gather and store network data◦ Netflow is a common◦ It gathers data about the traffic traversing a
router or switch Probes are active collectors
◦ They can trigger events and collect the responses
Collectors and Probes
Provide information regarding suspicious activity on a network, such as◦ break-ins to routers or servers and◦ denial-of-service attacks
IDS listen◦ for alarms◦ inspect activity logs and◦ observe load patterns to determine if a network
has been compromised
Intrusion Detection Systems
Performance Analysis Systems Enable users to analyze traffic and
performance data to recognize trends and traffic patterns
Alarm Management Systems Collect, monitor, and group large volumes
of data that pertain to alarms that are triggered by different events on the network
May be provide an initial diagnosis of the cause of an alarm
Performance and Alarms
Trouble Ticket Systems Support network problem resolution Usually generated by users of the network who
experience a problem Assign tickets, escalate tickets that take too long to
resolve, and report statistics about the resolution process
Work Order Systems Assign and track maintenance jobs in a network Help organize workforce that performs jobs Track the maintenance process
Trouble Ticket and Work Oders
Help manage execution of predefined processes that consist of multiple steps and different owners
Not specific to networks Based upon concept of finite state machines Events are managed by a workflow engine
Workflow Management Systems and Workflow Engines
Inventory Systems Used to track assets which may be either
physical or services (such as a phone service)
Service Provisioning Systems Facilitate the deployment of services, such
as DSL, over a network Typically found in operational support
environments of large service providers
Inventory and Service Provisioning
Service Order-Management Systems◦ Used to manage orders for customers of large
service providers, generally not found in enterprise environments
◦ Manages workflows and processes of an organization
Billing Systems◦ Essential for collections of revenues◦ Analyze accounting and usage data to identify
which communications services were provided to whom
◦ Can be helpful in fraud detection
Order Management and Billing
Three scenarios illustrating how networks are managed in practice and the variety of tasks that are involved were discussed
The service provider scenario emphasized workflows, processes, and interactions
The medium-size enterprise scenario was characterized by a variety of tasks that had to be performed by one individual and a greater reliance on the individual expertise and intuition
The Internet Data Center scenario focused on the planning phase of a network’s life cycle as well as management practices for both the network and the devices and applications connected to it
The scenarios illustrate that network management involves management technology as well as organizational and human factors
In each case personnel were supported by a variety of tools A wide variety of different tools exist Running the largest, most complex networks usually involves
hundreds of management systems and applications
Chapter Summary