Book Image

AWS Certified Solutions Architect Study Guide: Associate SAA-C01 Exam - Second Edition

By : Ben Piper, David Clinton
Book Image

AWS Certified Solutions Architect Study Guide: Associate SAA-C01 Exam - Second Edition

By: Ben Piper, David Clinton

Overview of this book

The?AWS Certified Solutions Architect Study Guide: Associate (SAA-C01) Exam?enables you to validate your skills, increase your competitive advantage, and take the next step on your career path. Comprehensive and up-to-date content and superior study tools make this guide a must-have resource for those seeking AWS Solutions Architect – Associate certification. The?AWS Certified Solutions Architect Study Guide: Associate (SAA-C01) Exam?is your complete and fully updated resource to the AWS Solutions Architect - Associate certification. This invaluable Sybex study guide covers all relevant aspects of the AWS Solutions Architect job role, including mapping multi-tier architectures to AWS services, loose coupling and stateless systems, applying AWS security features, deploying and managing services, designing large scale distributed systems, and many more. Written by two AWS subject-matter experts, this self-study guide and reference provides all the tools and information necessary to master the exam, earn your certification, and gain insights into the job of an AWS Solutions Architect. Efficient and logical presentation of exam objectives allows for flexible study of topics, and powerful learning tools increase comprehension and retention of key exam elements. Practice questions, chapter reviews, and detailed examination of essential concepts fully prepare you for the AWS Solutions Architect – Associate certification.
Table of Contents (10 chapters)
Free Chapter
1
Acknowledgments
2
About the Authors
7
Index
8
Comprehensive Online Learning Environment
9
Wiley End User License Agreement

Chapter 9: The Reliability Pillar

  • 1. C. 99.95 percent availability translates to about 22 minutes of downtime per month, or 4 hours and 23 minutes per year. 99.999 percent availability is less than 30 seconds of downtime per month, but the question calls for the minimum level of availability. 99 percent yields more than 7 hours of downtime per month, while 99.9 percent is more than 43 minutes of downtime per month.
  • 2. A. The EC2 instances are redundant components, so to calculate their availability, you multiply the component failure rates and subtract the product from 100 percent. In this case, 100% – (1% × 1%) = 99.99%. Because the database represents a hard dependency, you multiply the availability of the EC2 instances by the availability of the RDS instance, which is 99 percent. In this case, 99.99% × 99% = 98.99%. A total availability of 99 percent may seem intuitive since it’s the availability of each component, but because the redundant EC2 instances have...