Red Hat ENTERPRISE LINUX 4 - INTRODUCTION TO SYSTEM ADMINISTRATION Administration Manual

Also see for ENTERPRISE LINUX 4 - DEVELOPER TOOLS GUIDE: Installation guide Installation guide Tuning guide Installation guide Manual

Contents

6 Chapter 1. The Philosophy of System Administration• Time (often of critical importance when the time involves things such as the amount of time duringwhich system backups may take place)• Knowledge (whether it is stored in books, system documentation, or the brain of a person that hasworked at the company for the past twenty years)It is important to note is that it is highly valuable to take a complete inventory of those resourcesavailable to you and to keep it current — a lack of "situational awareness" when it comes to availableresources can often be worse than no awareness at all.1.5. Know Your UsersAlthough some people bristle at the term "users" (perhaps due to some system administrators’ use ofthe term in a derogatory manner), it is used here with no such connotation implied. Users are thosepeople that use the systems and resources for which you are responsible — no more, and no less. Assuch, they are central to your ability to successfully administer your systems; without understandingyour users, how can you understand the system resources they require?For example, consider a bank teller. A bank teller uses a strictly-defined set of applications and re-quires little in the way of system resources. A software engineer, on the other hand, may use manydifferent applications and always welcomes more system resources (for faster build times). Two en-tirely different users with two entirely different needs.Make sure you learn as much about your users as you can.1.6. Know Your BusinessWhether you work for a large, multinational corporation or a small community college, you must stillunderstand the nature of the business environment in which you work. This can be boiled down to onequestion:What is the purpose of the systems you administer?The key point here is to understand your systems’ purpose in a more global sense:• Applications that must be run within certain time frames, such as at the end of a month, quarter, oryear• The times during which system maintenance may be done• New technologies that could be used to resolve long-standing business problemsBy taking into account your organization’s business, you will find that your day-to-day decisions willbe better for your users, and for you.1.7. Security Cannot be an AfterthoughtNo matter what you might think about the environment in which your systems are running, you cannottake security for granted. Even standalone systems not connected to the Internet may be at risk (al-though obviously the risks will be different from a system that has connections to the outside world).Therefore, it is extremely important to consider the security implications of everything you do. Thefollowing list illustrates the different kinds of issues you should consider:• The nature of possible threats to each of the systems under your care• The location, type, and value of the data on those systems