Expect The Unexpected; Red Hat Enterprise Linux-Specific Information; Automation - Red Hat ENTERPRISE LINUX 3 - INTRODUCTION TO SYSTEM ADMINISTRATION Administration Manual

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fantastic administrator would be caught flat-footed. The reason? Our fantastic administrator failed to
plan ahead.
Certainly no one can predict the future with 100% accuracy. However, with a bit of awareness it is
easy to read the signs of many changes:
An offhand mention of a new project gearing up during that boring weekly staff meeting is a sure
•
sign that you will likely need to support new users in the near future
Talk of an impending acquisition means that you may end up being responsible for new (and pos-
•
sibly incompatible) systems in one or more remote locations
Being able to read these signs (and to respond effectively to them) makes life easier for you and your
users.

1.9. Expect the Unexpected

While the phrase "expect the unexpected" is trite, it reflects an underlying truth that all system admin-
istrators must understand:
There will be times when you are caught off-guard.
After becoming comfortable with this uncomfortable fact of life, what can a concerned system admin-
istrator do? The answer lies in flexibility; by performing your job in such a way as to give you (and
your users) the most options possible. Take, for example, the issue of disk space. Given that never
having sufficient disk space seems to be as much a physical law as the law of gravity, it is reasonable
to assume that at some point you will be confronted with a desperate need for additional disk space
right now.
What would a system administrator who expects the unexpected do in this case? Perhaps it is possible
to keep a few disk drives sitting on the shelf as spares in case of hardware problems
type could be quickly deployed
giving time to more permanently resolve the issue (by following the standard procedure for procuring
additional disk drives, for example).
By trying to anticipate problems before they occur, you will be in a position to respond more quickly
and effectively than if you let yourself be surprised.
1.10. Red Hat Enterprise Linux-Specific Information
This section describes information related to the philosophy of system administration that is specific
to Red Hat Enterprise Linux.

1.10.1. Automation

Automation of frequently-performed tasks under Red Hat Enterprise Linux requires knowledge of
several different types of technologies. First are the commands that control the timing of command or
script execution. The
Incorporating an easy-to-understand yet powerfully flexible time specification system,
schedule the execution of commands or scripts for recurring intervals ranging in length from minutes
2. And of course a system administrator that expects the unexpected would naturally use RAID (or related
technologies) to lessen the impact of a critical disk drive failing during production.
3. Again, system administrators that think ahead configure their systems to make it as easy as possible to quickly
add a new disk drive to the system.
3 on a temporary basis to address the short-term need for disk space,
and commands are most commonly used in these roles.
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Chapter 1. The Philosophy of System Administration
2 . A spare of this
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