Troubleshooting and maintenance 16–17
A complete treatise on troubleshooting is beyond the scope of this course. The same is
true of network troubleshooting. However, there are some general principles to follow
and a few utilities you should know how to use to tackle a troubleshooting attempt.
Divide and conquer—Whether you physically change things or just think about
them, dividing a problem into smaller pieces will often quickly lead you to the
source of a problem. Is everyone on the network having the same issues? Or, is
it just this station or just this segment? You might need to disconnect network
segments, remove potentially-flaky hardware, and so forth. Or, you might just
test some commands at various computers, ask questions, and so forth.
Find out what’s changed—When did it last work? What has happened since
then? Was new software or hardware installed? Were devices reconfigured? The
answers to these questions might lead you to the root of the problem. Or, you
might be able to work backward, undoing the changes until you get the network
Work methodically—Make one change at a time and test to see if you solved the
problem. If not, you should undo the change and try another approach. If you
change four things and functionality is restored, you probably won’t know which
of those changes actually solved the problem.