Review

Answering the following questions will reinforce key information presented in this chapter. If you’re unable to answer a question, review the appropriate lesson and then try the question again. Answers to the questions can be found in the appendix.

1. Define the following key terms: availability, failure, fault tolerance, manageability, reliability, and scalability.
2. What are the key architectural elements of an n-tier business Web site?
3. In the formula MTTR/MTTF, what do MTTR and MTTF refer to, how do they differ, and what’s the purpose of this ratio?
4. What types of failures can cause system outages?
5. You’re designing a highly available Web site. What are the three fundamental strategies that you should use?
6. You’re designing a highly available Web site and you’re specifically concerned about preventing application failures. What techniques should you use to reduce the chance of failures?