CCNP TSHOOT 642-832
Quick Reference
Chapter 1
Maintenance.............................................3
Chapter 2
Troubleshooting Methodology.............16
Chapter 3
Troubleshooting Tools...........................22
Chapter 4
Troubleshooting Switches ...................43
Chapter 5
Troubleshooting Routing ......................55
Chapter 6
Troubleshooting Security Features ....66
Brent Stewart
ciscopress.com
About the Author
Brent Stewart, CCNP, CCDP, CCSI, MCSE, is the manageer of Connectivity Services at CommScope. He is responsible
for designing and managing a large-scale worldwide voice, video, and data network. Previously he was a course director
for Global Knowledge, participated in the development of BSCI with Cisco, and has written and taught extensively on
CCNA and CCNP. Brent lives in Hickory, NC, with his beautiful wife, Karen, and their mischievous children Benjamin,
Kaitlyn, Madelyn, and William.
About the Technical Editor
‘Rhette (Margaret) Marsh, CCIE No. 17476 Routing and Switching, CCNP, CCDP, CCNA, CCDA, CISSP, Marsh has
been working in the networking and security industry for more than ten years and has extensive experience with internet-
work design, IPv6, forensics, and greyhat work. She currently is a design consultant for Cisco in San Jose, CA, and
works primarily with the Department of Defense and contractors. Prior to this, she worked extensively both in the finan-
cial industry as a routing and switching and design/security consultant and also in an attack attribution and orensics
context. ‘Rhette is working toward her Security and Design CCIEs. In her copious free time, she enjoys number theory,
arcane literature, cycling, hiking in the redwoods, sea kayaking, and her mellow cat, lexx.
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© 2010 Pearson Education, Inc. All rights reserved. This publication is protected by copyright. Please see page 69 for more details.
CCNP TSHOOT 642-832 Quick Reference by Brent Stewart
CHAPTER 1
Maintenance
Chapter 1
Maintenance
Maintenance might seem separate from the process of troubleshooting but imagine it as the other side of the same coin.
Any device that is well maintained will be more reliable, suffers fewer problems, and will be easier and quicker to repair.
Network owners, such as businesses and governments, want computer systems that are consistently available. Good trou-
bleshooting technique minimizes the length of time of an outage, but good maintenance technique reduces outages.
You must select the appropriate tools and techniques for the network you maintain, based on law, company policy, and
your experience. You need to understand, whichever elements you incorporate into your strategy, that a structured
approach to maintenance is a key part of reducing unplanned outages.
Methodology
Network maintenance involves many different kinds of tasks, such as
n Installing new equipment
n Adjusting settings to support new service
n Securing the network
n Restoring service
n Backing up configs
n Planning new or upgraded service
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© 2010 Pearson Education, Inc. All rights reserved. This publication is protected by copyright. Please see page 69 for more details.
CCNP TSHOOT 642-832 Quick Reference by Brent Stewart
NOTE:
TSHOOT doesn’t assume
a specific approach to
maintenance.
Organizations might
produce documentation
and monitor their
networks in unique ways.
TSHOOT focuses on
understanding the general
practices that are used to
successfully maintain a
network.
CHAPTER 1
Maintenance
n Building redundancy and disaster recovery
n Documentation
n Responding to user complaints
Many activities are reactive, and it is easy for interrupt-driven issues to monopolize your time. Defining a preventative
maintenance schedule can help you avoid “firefighting.” Taking a more structured approach—as opposed for waiting for
the phone to ring—can also help you recognize problems earlier and respond to them more efficiently. A broader perspec-
tive toward the network also provides an opportunity to align costs with the organization’s goals and budget effectively.
Several generic maintenance frameworks are available. Some organizations embrace a specific methodology, but many
organizations pick, choose, and customize pieces that fit their environment. The important point is to have a documented
approach to maintenance. If your organization doesn’t have a documented strategy, you might want to research some of
these models.
n IT Infrastructure Library (ITIL)
n FCAPS
n Telecommunications Management Network (TMN)
n Cisco Lifecycle Services/PPDIOO
n Microsoft Operations Framework
After you choose a specific model, map the model onto processes you can use to maintain the network and then select the
tools that you use.
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© 2010 Pearson Education, Inc. All rights reserved. This publication is protected by copyright. Please see page 69 for more details.
CCNP TSHOOT 642-832 Quick Reference by Brent Stewart
CHAPTER 1
Maintenance
Common Tasks
Although organizations that own networks have different expectations, the management of every network still includes
some basic components. Planning and accomplishing these tasks repetitively and competently is a key to successful
network management.
Some common tasks include
n Adds, moves, and changes
n Compiling documentation
n Preparing for disaster
n Capacity planning/utilization monitoring
n Troubleshooting
n Proactive scheduled maintenance
n Rollback plans for each change
n Lab testing in a controlled environment before each change is put into production to minimize risk
Preventative maintenance is the process of anticipating potential sources of failure and dealing with the problem before it
occurs. It is probably not possible to anticipate every source of failure, but careful thought might help you identify candi-
dates. One technique to identify issues is to look at prior records of trouble, such as trouble tickets, ISP records, network
monitoring systems, or purchase records. Use this information to categorize and rank the experience of your network.
Organizations are typically willing to accept small periods of scheduled downtime to offset the probability of long
periods of unscheduled downtime. Using the data collected from your experience, consider the steps that can be taken
during this window of time. Operating systems can be patched or upgraded to more stable and secure versions.
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© 2010 Pearson Education, Inc. All rights reserved. This publication is protected by copyright. Please see page 69 for more details.
CCNP TSHOOT 642-832 Quick Reference by Brent Stewart
