Transcript Document

Chapter 14: Troubleshooting and Problem
Resolution
Help Desk
• It is likely that your first job working with a LAN will be as
help desk support. Almost every System Administrator has
worked their way up from the help desk and most consider it
a rite of passage.
• Working on the help desk requires the ability to communicate
with non-technical users. It also requires patience and an
even temper as users will often vent their frustrations on
support personnel. If a particular user is continually rude,
bring the issue up with your manager.
• Some organizations have a job tracking database. Checking a
caller’s prior job history might give clues to the problem that
they are experiencing.
Help Desk
• It is important to know when you should escalate a problem
to someone higher up, such as a system administrator. Help
desk personnel are not expected to be able to solve all
problems.
• Don’t expect to be able to solve every problem instantly over
the phone. You may have to tell a user that you will call them
back so that you can research their problem.
Troubleshooting
• Troubleshooting skills develop over time. Someone working on a
help desk for some time is able to more quickly diagnose problems
because they have seen most of them before.
• It can be difficult to
diagnose a problem
over the phone as
many users don’t have
the understanding to
explain issues in more
than general terms such
as “I can’t get the
Internet”.
Troubleshooting
As you become more experienced, you learn how to ask simpler
questions of users that will allow them to provide you with the
information you need. This often involves getting them to describe
what they see, or whether or not a simple task works. Try to avoid
getting users to perform complex diagnostic tasks as it rarely works
out well.
Information Sources
• One of the most important skills any person working with LAN
equipment needs is the ability to research a solution.
• It is extremely likely that someone else in the world has
encountered exactly the same problem, has documented a solution,
and posted that solution to a Web site.
• Microsoft has Technet, http://www.microsoft.com/technet and the
Knowledge Base, http://support.microsoft.com. Each has a very
large database of troubleshooting and informational articles about
Microsoft products.
• The Linux Documentation Project http://www.tldp.org contains a
large archive of HOWTO articles and FAQs (Frequently Asked
Questions).
Information Sources
• USENET Archive at http://groups.google.com contains all posts
to usenet, which has many troubleshooting newsgroups.
• Operating systems have less extensive online help files. Generally,
these help files explain how to perform a particular task, but do not
contain much in the way of useful troubleshooting information.
• Books about a particular operating system or product can be
helpful, but are often expensive. Some publishers offer
subscription-based technical libraries that allow you to search
thousands of books at a time for a solution to a problem.
Troubleshooting Hardware
• If hardware is faulty, you are almost always going to have to
replace it. Before you do that, install the most up-to-date device
driver.
• Many large organizations negotiate an agreement with their
supplier about hardware support. If a component fails, a
replacement will be sent out.
• You should have hardware support agreements for your
organization’s servers with the vendor. For important servers, keep
a supply of replacement parts on hand. Hot swappable components
aren’t as useful if you don’t have anything to hot swap them with.
Troubleshooting Hardware
• Sometimes diagnosis is easy. If you can’t see anything on the
screen, but it is clear that the computer is actually functioning, the
problem will lie with your monitor or your graphics card. To find
out which, connect a monitor you know works and see what
happens.
• Sometimes diagnosis is difficult. Difficulty connecting to the
network might be the result of a bad network card, bad IP address
configuration, a broken twisted pair cable, a broken switch or
router. You can rule out the network infrastructure being the
problem by plugging another computer into the same network
point. If the computer was working until recently and your
organization uses DHCP, you should suspect the network card.
Troubleshooting the Network
• If one user has a problem, the problem is likely local to the user. If
many users have a problem, there is likely something wrong with
your network.
• Each computer on the network should respond to a PING request.
PING is a utility present on every operating system. At a command
prompt, type PING IP_ADDRESS. If that works, attempt PING
FQDN. If one works and the other doesn’t, you should suspect a
problem with your DNS server.
• If you can PING 127.0.0.1, which is the loopback address, it means
that your computer’s network software works. If you can not PING
127.0.0.1 successfully, you may have to reinstall the network
software.
Troubleshooting the Network
• The TRACERT or TRACEROUTE utility can be used to check
connectivity over longer distances. If you can access some locations
on the network, but not others, you can use TRACEROUTE to
determine which link in the chain is broken.
• The Windows Server 2003 support tools include a utility called
NETDIAG. This utility performs a thorough set of tests on a
network. Useful for more complex network troubleshooting.
Software Troubleshooting
• If software is misbehaving after functioning normally, you should
check if any new software has been installed on the problematic
computer. It may be that the two programs are incompatible. This is
one reason why you should test new programs in a development
environment before installing them on employee’s workstations.
• Check the vendor’s site for the latest patch or service pack to the
software. Install the patch and see if that resolves the issue.
• Remember that it usually doesn’t take all that long to uninstall and
then reinstall a program. It may take 20 minutes to do a reinstall,
but that is better than spending an hour looking through diagnostic
information and not getting anywhere.
• How you treat desktop applications is very different compared to
how you treat a network server such as Exchange Server 2003. Be
very careful when making any changes to configurations as it may
result in all of the organization’s users being unable to access e-mail.
Summary
• Troubleshooting is detective work. Sometimes the culprit is
obvious and other times it will take time and research to
reveal.
• The Internet can be a fantastic resource for troubleshooting.
• When troubleshooting the network, use utilities such as PING
and TRACERT. Also try to determine if other users are
suffering the same problems.
• When troubleshooting software, install any available patches
before reinstalling the software.
• Be careful making configuration changes to network services
such as Exchange.
Discussion Questions
 Why is TCP/IP configuration unlikely to be a problem if
hosts use DHCP?
 What steps could you take to help determine that a fault lies
with a network card?
 Why do help desk staff need to be patient and eventempered?
 Why are you more likely to find troubleshooting
information on the Internet rather than in help files?