Use AWS Cheatsheets – I also found the cheatsheets provided by Tutorials Dojo very helpful. In my opinion, it is better than Jayendrapatil Patil’s blog since it contains more updated information that complements your review notes. #AWS Cheat Sheet
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Watch this exam readiness 3hr video, it very recent webinar this provides what is expected in the exam. #AWS Exam Prep Video
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Start off watching Ryan’s videos. Try and completely focus on the hands on. Take your time to understand what you are trying to learn and achieve in those LAB Sessions. #AWS Exam Prep Video
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Do not rush into completing the videos. Take your time and hone the basics. Focus and spend a lot of time for the back bone of AWS infrastructure – Compute/EC2 section, Storage (S3/EBS/EFS), Networking (Route 53/Load Balancers), RDS, VPC, Route 3. These sections are vast, with lot of concepts to go over and have loads to learn. Trust me you will need to thoroughly understand each one of them to ensure you pass the certification comfortably. #AWS Exam Prep Video
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Make sure you go through resources section and also AWS documentation for each components. Go over FAQs. If you have a question, please post it in the community. Trust me, each answer here helps you understand more about AWS. #AWS Faqs
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Like any other product/service, each AWS offering has a different flavor. I will take an example of EC2 (Spot/Reserved/Dedicated/On Demand etc.). Make sure you understand what they are, what are the pros/cons of each of these flavors. Applies for all other offerings too. #AWS Services
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Follow Neal K Davis on Linkedin and Read his updates about DVA-C01 #AWS Services
What is the AWS Certified Developer Associate Exam?
The AWS Certified Developer – Associate examination is intended for individuals who perform a development role and have one or more years of hands-on experience developing and maintaining an AWS-based application. It validates an examinee’s ability to:
Demonstrate an understanding of core AWS services, uses, and basic AWS architecture best practices
Demonstrate proficiency in developing, deploying, and debugging cloud-based applications using AWS
There are two types of questions on the examination:
Multiple-choice: Has one correct response and three incorrect responses (distractors).
Provide implementation guidance based on best practices to the organization throughout the lifecycle of the project.
Select one or more responses that best complete the statement or answer the question. Distractors, or incorrect answers, are response options that an examinee with incomplete knowledge or skill would likely choose. However, they are generally plausible responses that fit in the content area defined by the test objective. Unanswered questions are scored as incorrect; there is no penalty for guessing.
To succeed with the real exam, do not memorize the answers below. It is very important that you understand why a question is right or wrong and the concepts behind it by carefully reading the reference documents in the answers.
Understand bastion hosts, and which subnet one might live on. Bastion hosts are instances that sit within your public subnet and are typically accessed using SSH or RDP. Once remote connectivity has been established with the bastion host, it then acts as a ‘jump’ server, allowing you to use SSH or RDP to login to other instances (within private subnets) deeper within your network. When properly configured through the use of security groups and Network ACLs, the bastion essentially acts as a bridge to your private instances via the Internet.” Bastion Hosts
3
Know the difference between Directory Service’s AD Connector and Simple AD. Use Simple AD if you need an inexpensive Active Directory–compatible service with the common directory features. AD Connector lets you simply connect your existing on-premises Active Directory to AWS. AD Connector and Simple AD
4
Know how to enable cross-account access with IAM: To delegate permission to access a resource, you create an IAM role that has two policies attached. The permissions policy grants the user of the role the needed permissions to carry out the desired tasks on the resource. The trust policy specifies which trusted accounts are allowed to grant its users permissions to assume the role. The trust policy on the role in the trusting account is one-half of the permissions. The other half is a permissions policy attached to the user in the trusted account that allows that user to switch to, or assume the role. Enable cross-account access with IAM
Know which services allow you to retain full admin privileges of the underlying EC2 instances EC2 Full admin privilege
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Know When Elastic IPs are free or not: If you associate additional EIPs with that instance, you will be charged for each additional EIP associated with that instance per hour on a pro rata basis. Additional EIPs are only available in Amazon VPC. To ensure efficient use of Elastic IP addresses, we impose a small hourly charge when these IP addresses are not associated with a running instance or when they are associated with a stopped instance or unattached network interface. When are AWS Elastic IPs Free or not?
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Know what are the four high level categories of information Trusted Advisor supplies. #AWS Trusted advisor
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Know how to troubleshoot a connection time out error when trying to connect to an instance in your VPC. You need a security group rule that allows inbound traffic from your public IP address on the proper port, you need a route that sends all traffic destined outside the VPC (0.0.0.0/0) to the Internet gateway for the VPC, the network ACLs must allow inbound and outbound traffic from your public IP address on the proper port, etc. #AWS Connection time out error
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Be able to identify multiple possible use cases and eliminate non-use cases for SWF. #AWS
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Understand how you might set up consolidated billing and cross-account access such that individual divisions resources are isolated from each other, but corporate IT can oversee all of it. #AWS Set up consolidated billing
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Know how you would go about making changes to an Auto Scaling group, fully understanding what you can and can’t change. “You can only specify one launch configuration for an Auto Scaling group at a time, and you can’t modify a launch configuration after you’ve created it. Therefore, if you want to change the launch configuration for your Auto Scaling group, you must create a launch configuration and then update your Auto Scaling group with the new launch configuration. When you change the launch configuration for your Auto Scaling group, any new instances are launched using the new configuration parameters, but existing instances are not affected. #AWS Make Change to Auto Scaling group
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Know how you would go about making changes to an Auto Scaling group, fully understanding what you can and can’t change. “You can only specify one launch configuration for an Auto Scaling group at a time, and you can’t modify a launch configuration after you’ve created it. Therefore, if you want to change the launch configuration for your Auto Scaling group, you must create a launch configuration and then update your Auto Scaling group with the new launch configuration. When you change the launch configuration for your Auto Scaling group, any new instances are launched using the new configuration parameters, but existing instances are not affected. #AWS Make Change to Auto Scaling group
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Know which field you use to run a script upon launching your instance. #AWS User data script
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Know how DynamoDB (durable, and you can pay for strong consistency), Elasticache (great for speed, not so durable), and S3 (eventual consistency results in lower latency) compare to each other in terms of durability and low latency. #AWS DynamoDB consistency
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Know the difference between bucket policies, IAM policies, and ACLs for use with S3, and examples of when you would use each. “With IAM policies, companies can grant IAM users fine-grained control to their Amazon S3 bucket or objects while also retaining full control over everything the users do. With bucket policies, companies can define rules which apply broadly across all requests to their Amazon S3 resources, such as granting write privileges to a subset of Amazon S3 resources. Customers can also restrict access based on an aspect of the request, such as HTTP referrer and IP address. With ACLs, customers can grant specific permissions (i.e. READ, WRITE, FULL_CONTROL) to specific users for an individual bucket or object. #AWS Difference between bucket policies
Understand how you can use ELB cross-zone load balancing to ensure even distribution of traffic to EC2 instances in multiple AZs registered with a load balancer. #AWS ELB cross-zone load balancing
Spot instances are good for cost optimization, even if it seems you might need to fall back to On-Demand instances if you wind up getting kicked off them and the timeline grows tighter. The primary (but still not only) factor seems to be whether you can gracefully handle instances that die on you–which is pretty much how you should always design everything, anyway! #AWS Spot instances
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The term “use case” is not the same as “function” or “capability”. A use case is something that your app/system will need to accomplish, not just behaviour that you will get from that service. In particular, a use case doesn’t require that the service be a 100% turnkey solution for that situation, just that the service plays a valuable role in enabling it. #AWS use case
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There might be extra, unnecessary information in some of the questions (red herrings), so try not to get thrown off by them. Understand what services can and can’t do, but don’t ignore “obvious”-but-still-correct answers in favour of super-tricky ones. #AWS Exam Answers: Distractors
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If you don’t know what they’re trying to ask, in a question, just move on and come back to it later (by using the helpful “mark this question” feature in the exam tool). You could easily spend way more time than you should on a single confusing question if you don’t triage and move on. #AWS Exa: Skip Questions that are vague and come back to them later
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Some exam questions required you to understand features and use cases of: VPC peering, cross-account access, DirectConnect, snapshotting EBS RAID arrays, DynamoDB, spot instances, Glacier, AWS/user security responsibilities, etc. #AWS
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The 30 Day constraint in the S3 Lifecycle Policy before transitioning to S3-IA and S3-One Zone IA storage classes #AWS S3 lifecycle policy
Watch Acloud Guru Videos Lectures while commuting / lunch break – Reschedule the exam if you are not yet ready #AWS ACloud Guru
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Watch Linux Academy Videos Lectures while commuting / lunch break – Reschedule the exam if you are not yet ready #AWS Linux Academy
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Watch Udemy Videos Lectures while commuting / lunch break – Reschedule the exam if you are not yet ready #AWS Linux Academy
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The Udemy practice test interface is good that it pinpoints your weak areas, so what I did was to re-watch all the videos that I got the wrong answers. Since I was able to gauge my exam readiness, I decided to reschedule my exam for 2 more weeks, to help me focus on completing the practice tests. #AWS Udemy
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Use AWS Cheatsheets – I also found the cheatsheets provided by Tutorials Dojo very helpful. In my opinion, it is better than Jayendrapatil Patil’s blog since it contains more updated information that complements your review notes. #AWS Cheat Sheet
40
Watch this exam readiness 3hr video, it very recent webinar this provides what is expected in the exam. #AWS Exam Prep Video
41
Start off watching Ryan’s videos. Try and completely focus on the hands on. Take your time to understand what you are trying to learn and achieve in those LAB Sessions. #AWS Exam Prep Video
42
Do not rush into completing the videos. Take your time and hone the basics. Focus and spend a lot of time for the back bone of AWS infrastructure – Compute/EC2 section, Storage (S3/EBS/EFS), Networking (Route 53/Load Balancers), RDS, VPC, Route 3. These sections are vast, with lot of concepts to go over and have loads to learn. Trust me you will need to thoroughly understand each one of them to ensure you pass the certification comfortably. #AWS Exam Prep Video
43
Make sure you go through resources section and also AWS documentation for each components. Go over FAQs. If you have a question, please post it in the community. Trust me, each answer here helps you understand more about AWS. #AWS Faqs
44
Like any other product/service, each AWS offering has a different flavor. I will take an example of EC2 (Spot/Reserved/Dedicated/On Demand etc.). Make sure you understand what they are, what are the pros/cons of each of these flavors. Applies for all other offerings too. #AWS Services
45
Ensure to attend all quizzes after each section. Please do not treat these quizzes as your practice exams. These quizzes are designed to mostly test your knowledge on the section you just finished. The exam itself is designed to test you with scenarios and questions, where in you will need to recall and apply your knowledge of different AWS technologies/services you learn over multiple lectures. #AWS Services
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I, personally, do not recommend to attempt a practice exam or simulator exam until you have done all of the above. It was a little overwhelming for me. I had thoroughly gone over the videos. And understood the concepts pretty well, but once I opened exam simulator I felt the questions were pretty difficult. I also had a feeling that videos do not cover lot of topics. But later I realized, given the vastness of AWS Services and offerings it is really difficult to encompass all these services and their details in the course content. The fact that these services keep changing so often, does not help #AWS Services
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Go back and make a note of all topics, that you felt were unfamiliar for you. Go through the resources section and fiund links to AWS documentation. After going over them, you shoud gain at least 5-10% more knowledge on AWS. Have expectations from the online courses as a way to get thorough understanding of basics and strong foundations for your AWS knowledge. But once you are done with videos. Make sure you spend a lot of time on AWS documentation and FAQs. There are many many topics/sub topics which may not be covered in the course and you would need to know, atleast their basic functionalities, to do well in the exam. #AWS Services
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Once you start taking practice exams, it may seem really difficult at the beginning. So, please do not panic if you find the questions complicated or difficult. IMO they are designed or put in a way to sound complicated but they are not. Be calm and read questions very carefully. In my observation, many questions have lot of information which sometimes is not relevant to the solution you are expected to provide. Read the question slowly and read it again until you understand what is expected out of it. #AWS Services
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With each practice exam you will come across topics that you may need to scale your knowledge on or learn them from scratch. #AWS Services
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With each test and the subsequent revision, you will surely feel more confident.
There are 130 mins for questions. 2 mins for each question which is plenty of time.
At least take 8-10 practice tests. The ones on udemy/tutorialdojo are really good. If you are a acloudguru member. The exam simulator is really good.
Manage your time well. Keep patience. I saw someone mention in one of the discussions that do not under estimate the mental focus/strength needed to sit through 130 mins solving these questions. And it is really true.
Do not give away or waste any of those precious 130 mins. While answering flag/mark questions you think you are not completely sure. My advice is, even if you finish early, spend your time reviewing the answers. I could review 40 of my answers at the end of test. And I at least rectified 3 of them (which is 4-5% of total score, I think)
So in short – Put a lot of focus on making your foundations strong. Make sure you go through AWS Documentation and FAQs. Try and envision how all of the AWS components can fit together and provide an optimal solution. Keep calm. This video gives outline about exam, must watch before or after Ryan’s course.#AWS Services
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Walking you through how to best prepare for the AWS Certified Solutions Architect Associate SAA-C02 exam in 5 steps:
1. Understand the exam blueprint
2. Learn about the new topics included in the SAA-C02 version of the exam
3. Use the many FREE resources available to gain and deepen your knowledge
4. Enroll in our hands-on video course to learn AWS in depth
5. Use practice tests to fully prepare yourself for the exam and assess your exam readiness AWS CERTIFIED SOLUTIONS ARCHITECT SAA-C02 : HOW TO BEST PREPARE IN 5 STEPS
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Storage:
1. Know your different Amazon S3 storage tiers! You need to know the use cases, features and limitations, and relative costs; e.g. retrieval costs.
2. Amazon S3 lifecycle policies is also required knowledge — there are minimum storage times in certain tiers that you need to know.
3. For Glacier, you need to understand what it is, what it’s used for, and what the options are for retrieval times and fees.
4. For the Amazon Elastic File System (EFS), make sure you’re clear which operating systems you can use with it (just Linux).
5. For the Amazon Elastic Block Store (EBS), make sure you know when to use the different tiers including instance stores; e.g. what would you use for a datastore that requires the highest IO and the data is distributed across multiple instances? (Good instance store use case)
6. Learn about Amazon FSx. You’ll need to know about FSx for Windows and Lustre.
7. Know how to improve Amazon S3 performance including using CloudFront, and byte-range fetches — check out this whitepaper.
8. Make sure you understand about Amazon S3 object deletion protection options including versioning and MFA delete. AWS CERTIFIED SOLUTIONS ARCHITECT SAA-C02 : HOW TO BEST PREPARE IN 5 STEPS
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Compute:
1. You need to have a good understanding of the options for how to scale an Auto Scaling Group using metrics such as SQS queue depth, or numbers of SNS messages.
2. Know your different Auto Scaling policies including Target Tracking Policies.
3. Read up on High Performance Computing (HPC) with AWS. You’ll need to know about Amazon FSx with HPC use cases.
4. Know your placement groups. Make sure you can differentiate between spread, cluster and partition; e.g. what would you use for lowest latency? What about if you need to support an app that’s tightly coupled? Within an AZ or cross AZ?
5. Make sure you know the difference between Elastic Network Adapters (ENAs), Elastic Network Interfaces (ENIs) and Elastic Fabric Adapters (EFAs).
6. For the Amazon Elastic Container Service (ECS), make sure you understand how to assign IAM policies to ECS for providing S3 access. How can you decouple an ECS data processing process — Kinesis Firehose or SQS?
7. Make sure you’re clear on the different EC2 pricing models including Reserved Instances (RI) and the different RI options such as scheduled RIs.
8. Make sure you know the maximum execution time for AWS Lambda (it’s currently 900 seconds or 15 minutes). AWS CERTIFIED SOLUTIONS ARCHITECT SAA-C02 : HOW TO BEST PREPARE IN 5 STEPS
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Network
1. Understand what AWS Global Accelerator is and its use cases.
2. Understand when to use CloudFront and when to use AWS Global Accelerator.
3. Make sure you understand the different types of VPC endpoint and which require an Elastic Network Interface (ENI) and which require a route table entry.
4. You need to know how to connect multiple accounts; e.g. should you use VPC peering or a VPC endpoint?
5. Know the difference between PrivateLink and ClassicLink.
6. Know the patterns for extending a secure on-premises environment into AWS.
7. Know how to encrypt AWS Direct Connect (you can use a Virtual Private Gateway / AWS VPN).
8. Understand when to use Direct Connect vs Snowball to migrate data — lead time can be an issue with Direct Connect if you’re in a hurry.
9. Know how to prevent circumvention of Amazon CloudFront; e.g. Origin Access Identity (OAI) or signed URLs / signed cookies. AWS CERTIFIED SOLUTIONS ARCHITECT SAA-C02 : HOW TO BEST PREPARE IN 5 STEPS
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Databases
1. Make sure you understand Amazon Aurora and Amazon Aurora Serverless.
2. Know which RDS databases can have Read Replicas and whether you can read from a Multi-AZ standby.
3. Know the options for encrypting an existing RDS database; e.g. only at creation time otherwise you must encrypt a snapshot and create a new instance from the snapshot.
4. Know which databases are key-value stores; e.g. Amazon DynamoDB. AWS CERTIFIED SOLUTIONS ARCHITECT SAA-C02 : HOW TO BEST PREPARE IN 5 STEPS
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Application Integration
1. Make sure you know the use cases for the Amazon Simple Queue Service (SQS), and Simple Notification Service (SNS).
2. Understand the differences between Amazon Kinesis Firehose and SQS and when you would use each service.
3. Know how to use Amazon S3 event notifications to publish events to SQS — here’s a good “How To” article. AWS CERTIFIED SOLUTIONS ARCHITECT SAA-C02 : HOW TO BEST PREPARE IN 5 STEPS
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Management and Governance
1. You’ll need to know about AWS Organizations; e.g. how to migrate an account between organizations.
2. For AWS Organizations, you also need to know how to restrict actions using service control policies attached to OUs.
3. Understand what AWS Resource Access Manager is. AWS CERTIFIED SOLUTIONS ARCHITECT SAA-C02 : HOW TO BEST PREPARE IN 5 STEPS
The AWS Certified Solution Architect Associate Examination reparation and Readiness Quiz App (SAA-C01, SAA-C01, SAA) Prep App helps you prepare and train for the AWS Certification Solution Architect Associate Exam with various questions and answers dumps.
This App provide updated Questions and Answers, an Intuitive Responsive Interface allowing to browse questions horizontally and browse tips and resources vertically after completing a quiz.
Features:
100+ Questions and Answers updated frequently to get you AWS certified.
Quiz with score tracker, countdown timer, highest score saving. Vie Answers after completing the quiz for each category.
Ability to navigate through questions for each category using next and previous button.
Resource info page about the answer for each category and Top 60 Tips to succeed in the exam.
Prominent Cloud Evangelist latest tweets and Technology Latest News Feed
The app helps you study and practice from your mobile device with an intuitive interface.
SAA-C01 and SAA-C02 compatible
Resource info page about the answer for each category.
Helps you study and practice from your mobile device with an intuitive interface.
The questions and Answers are divided in 4 categories:
Design High Performing Architectures,
Design Cost Optimized Architectures,
Design Secure Applications And Architectures,
Design Resilient Architecture,
The questions and answers cover the following topics: AWS VPC, S3, DynamoDB, EC2, ECS, Lambda, API Gateway, CloudWatch, CloudTrail, Code Pipeline, Code Deploy, TCO Calculator, AWS S3, AWS DynamoDB, CloudWatch , AWS SES, Amazon Lex, AWS EBS, AWS ELB, AWS Autoscaling , RDS, Aurora, Route 53, Amazon CodeGuru, Amazon Bracket, AWS Billing and Pricing, AWS Simply Monthly Calculator, AWS cost calculator, Ec2 pricing on-demand, AWS Pricing, AWS Pay As You Go, AWS No Upfront Cost, Cost Explorer, AWS Organizations, Consolidated billing, Instance Scheduler, on-demand instances, Reserved instances, Spot Instances, CloudFront, Web hosting on S3, S3 storage classes, AWS Regions, AWS Availability Zones, Trusted Advisor, Various architectural Questions and Answers about AWS, AWS SDK, AWS EBS Volumes, EC2, S3, Containers, KMS, AWS read replicas, Cloudfront, API Gateway, AWS Snapshots, Auto shutdown Ec2 instances, High Availability, RDS, DynamoDB, Elasticity, AWS Virtual Machines, AWS Caching, AWS Containers, AWS Architecture, AWS Ec2, AWS S3, AWS Security, AWS Lambda, Bastion Hosts, S3 lifecycle policy, kinesis sharing, AWS KMS, Design High Performing Architectures, Design Cost Optimized Architectures, Design Secure Applications And Architectures, Design Resilient Architecture, AWS vs Azure vs Google Cloud, Resources, Questions, AWS, AWS SDK, AWS EBS Volumes, AWS read replicas, Cloudfront, API Gateway, AWS Snapshots, Auto shutdown Ec2 instances, High Availability, RDS, DynamoDB, Elasticity, AWS Virtual Machines, AWS Caching, AWS Containers, AWS Architecture, AWS Ec2, AWS S3, AWS Security, AWS Lambda, Load Balancing, DynamoDB, EBS, Multi-AZ RDS, Aurora, EFS, DynamoDB, NLB, ALB, Aurora, Auto Scaling, DynamoDB(latency), Aurora(performance), Multi-AZ RDS(high availability), Throughput Optimized EBS (highly sequential), SAA-CO1, SAA-CO2, Cloudwatch, CloudTrail, KMS, ElasticBeanstalk, OpsWorks, RPO vs RTO, HA vs FT, Undifferentiated Heavy Lifting, Access Management Basics, Shared Responsibility Model, Cloud Service Models, etc…
The resources sections cover the following areas: Certification, AWS training, Mock Exam Preparation Tips, Cloud Architect Training, Cloud Architect Knowledge, Cloud Technology, cloud certification, cloud exam preparation tips, cloud solution architect associate exam, certification practice exam, learn aws free, amazon cloud solution architect, question dumps, acloud guru links, tutorial dojo links, linuxacademy links, latest aws certification tweets, and post from reddit, quota, linkedin, medium, cloud exam preparation tips, aws cloud solution architect associate exam, aws certification practice exam, cloud exam questions, learn aws free, amazon cloud solution architect, amazon cloud certified solution architect associate exam questions, as certification dumps, google cloud, azure cloud, acloud, learn google cloud, learn azure cloud, cloud comparison, etc.
Abilities Validated by the Certification:
Effectively demonstrate knowledge of how to architect and deploy secure and robust applications on AWS technologies
Define a solution using architectural design principles based on customer requirements
Provide implementation guidance based on best practices to the organization throughout the life cycle of the project
Recommended Knowledge for the Certification:
One year of hands-on experience designing available, cost-effective, fault-tolerant, and scalable distributed systems on AWS.
Hands-on experience using compute, networking, storage, and database AWS services.
Hands-on experience with AWS deployment and management services.
Ability to identify and define technical requirements for an AWS-based application.
bility to identify which AWS services meet a given technical requirement.
Knowledge of recommended best practices for building secure and reliable applications on the AWS platform.
An understanding of the basic architectural principles of building in the AWS Cloud.
An understanding of the AWS global infrastructure.
An understanding of network technologies as they relate to AWS.
An understanding of security features and tools that AWS provides and how they relate to traditional services.
Note and disclaimer: We are not affiliated with AWS or Amazon or Microsoft or Google. The questions are put together based on the certification study guide and materials available online. We also receive questions and answers from anonymous users and we vet to make sure they are legitimate. The questions in this app should help you pass the exam but it is not guaranteed. We are not responsible for any exam you did not pass.
Important: To succeed with the real exam, do not memorize the answers in this app. It is very important that you understand why a question is right or wrong and the concepts behind it by carefully reading the reference documents in the answers.
What is the AWS Certified Solution Architect Associate Exam?
This exam validates an examinee’s ability to effectively demonstrate knowledge of how to architect and deploy secure and robust applications on AWS technologies. It validates an examinee’s ability to:
Define a solution using architectural design principles based on customer requirements.
Multiple-response: Has two correct responses out of five options.
There are two types of questions on the examination:
Multiple-choice: Has one correct response and three incorrect responses (distractors).
Provide implementation guidance based on best practices to the organization throughout the lifecycle of the project.
Select one or more responses that best complete the statement or answer the question. Distractors, or incorrect answers, are response options that an examinee with incomplete knowledge or skill would likely choose. However, they are generally plausible responses that fit in the content area defined by the test objective. Unanswered questions are scored as incorrect; there is no penalty for guessing.
To succeed with the real exam, do not memorize the answers below. It is very important that you understand why a question is right or wrong and the concepts behind it by carefully reading the reference documents in the answers.
Cloud computing is the new big thing in Information Technology. Everyone, every business will sooner or later adopt it, because of hosting cost benefits, scalability and more.
This blog outlines the Pros and Cons of Cloud Computing, Pros and Cons of Cloud Technology, Faqs, Facts, Questions and Answers Dump about cloud computing.
AWS Certified Cloud Practitioner Exam Prep PWA AppCloud Practitioner Exam Prep AWS vs Azure vs Google
What is cloud computing?
Cloud computing is an information technology paradigm that enables ubiquitous access to shared pools of configurable system resources and higher-level services that can be rapidly provisioned with minimal management effort, often over the Internet. Cloud computing relies on sharing of resources to achieve coherence and economies of scale, similar to a public utility. Simply put, cloud computing is the delivery of computing services including servers, storage, databases, networking, software, analytics, and intelligence—over the Internet (“the cloud”) to offer faster innovation, flexible resources, and economies of scale. You typically pay only for cloud services you use, helping you lower your operating costs, run your infrastructure more efficiently, and scale as your business needs change.
Stop spending money on running and maintaining data centers
Go global in minutes
Benefits of AWS Cloud Computing
Cost effective & Time saving: Cloud computing eliminates the capital expense of buying hardware and software and setting up and running on-site datacenters; the racks of servers, the round-the-clock electricity for power and cooling, and the IT experts for managing the infrastructure.
The ability to pay only for cloud services you use, helping you lower your operating costs.
Powerful server capabilities and Performance: The biggest cloud computing services run on a worldwide network of secure datacenters, which are regularly upgraded to the latest generation of fast and efficient computing hardware. This offers several benefits over a single corporate datacenter, including reduced network latency for applications and greater economies of scale.
Powerful and scalable server capabilities: The ability to scale elastically; That means delivering the right amount of IT resources—for example, more or less computing power, storage, bandwidth—right when they’re needed, and from the right geographic location.
SaaS ( Software as a service). Software as a service is a method for delivering software applications over the Internet, on demand and typically on a subscription basis. With SaaS, cloud providers host and manage the software application and underlying infrastructure, and handle any maintenance, like software upgrades and security patching. Users connect to the application over the Internet, usually with a web browser on their phone, tablet, or PC.
PaaS ( Platform as a service). Platform as a service refers to cloud computing services that supply an on-demand environment for developing, testing, delivering, and managing software applications. PaaS is designed to make it easier for developers to quickly create web or mobile apps, without worrying about setting up or managing the underlying infrastructure of servers, storage, network, and databases needed for development.
IaaS ( Infrastructure as a service). The most basic category of cloud computing services. With IaaS, you rent IT infrastructure—servers and virtual machines (VMs), storage, networks, operating systems—from a cloud provider on a pay-as-you-go basis
Serverless: Running complex Applications without a single server. Overlapping with PaaS, serverless computing focuses on building app functionality without spending time continually managing the servers and infrastructure required to do so. The cloud provider handles the setup, capacity planning, and server management for you. Serverless architectures are highly scalable and event-driven, only using resources when a specific function or trigger occurs.
Infrastructure provisioning as code, helps recreating same infrastructure by re-running the same code in a few click.
Automatic and Reliable Data backup and storage of data: Cloud computing makes data backup, disaster recovery, and business continuity easier and less expensive because data can be mirrored at multiple redundant sites on the cloud provider’s network.
Increase Productivity: On-site datacenters typically require a lot of “racking and stacking”—hardware setup, software patching, and other time-consuming IT management chores. Cloud computing removes the need for many of these tasks, so IT teams can spend time on achieving more important business goals.
Security: Many cloud providers offer a broad set of policies, technologies, and controls that strengthen your security posture overall, helping protect your data, apps, and infrastructure from potential threats.
Speed: Most cloud computing services are provided self service and on demand, so even vast amounts of computing resources can be provisioned in minutes, typically with just a few mouse clicks, giving businesses a lot of flexibility and taking the pressure off capacity planning. In a cloud computing environment, new IT resources are only a click away. This means that the time those resources are available to your developers is reduced from weeks to minutes. As a result, the organization experiences a dramatic increase in agility because the cost and time it takes to experiment and develop is lower
Go global in minutes
Easily deploy your application in multiple regions around the world with just a few clicks. This means that you can provide a lower latency and better experience for your customers simply and at minimal cost.
Privacy: Cloud computing poses privacy concerns because the service provider can access the data that is in the cloud at any time. It could accidentally or deliberately alter or delete information.Many cloud providers can share information with third parties if necessary for purposes of law and order without a warrant. That is permitted in their privacy policies, which users must agree to before they start using cloud services.
Security: According to the Cloud Security Alliance, the top three threats in the cloud are Insecure Interfaces and API’s, Data Loss & Leakage, and Hardware Failure—which accounted for 29%, 25% and 10% of all cloud security outages respectively. Together, these form shared technology vulnerabilities.
Ownership of Data: There is the problem of legal ownership of the data (If a user stores some data in the cloud, can the cloud provider profit from it?). Many Terms of Service agreements are silent on the question of ownership.
Limited Customization Options: Cloud computing is cheaper because of economics of scale, and—like any outsourced task—you tend to get what you get. A restaurant with a limited menu is cheaper than a personal chef who can cook anything you want.
Downtime: Technical outages are inevitable and occur sometimes when cloud service providers (CSPs) become overwhelmed in the process of serving their clients. This may result to temporary business suspension.
Security of stored data and data in transit may be a concern when storing sensitive data at a cloud storage provider[10]
Users with specific records-keeping requirements, such as public agencies that must retain electronic records according to statute, may encounter complications with using cloud computing and storage. For instance, the U.S. Department of Defense designated the Defense Information Systems Agency (DISA) to maintain a list of records management products that meet all of the records retention, personally identifiable information (PII), and security (Information Assurance; IA) requirements
Cloud storage is a rich resource for both hackers and national security agencies. Because the cloud holds data from many different users and organizations, hackers see it as a very valuable target.
Piracy and copyright infringement may be enabled by sites that permit filesharing. For example, the CodexCloud ebook storage site has faced litigation from the owners of the intellectual property uploaded and shared there, as have the GrooveShark and YouTube sites it has been compared to.
Public clouds: A cloud is called a “public cloud” when the services are rendered over a network that is open for public use. They are owned and operated by a third-party cloud service providers, which deliver their computing resources, like servers and storage, over the Internet. Microsoft Azure is an example of a public cloud. With a public cloud, all hardware, software, and other supporting infrastructure is owned and managed by the cloud provider. You access these services and manage your account using a web browser. For infrastructure as a service (IaaS) and platform as a service (PaaS), Amazon Web Services (AWS), Microsoft Azure and Google Cloud Platform (GCP) hold a commanding position among the many cloud companies.
Private cloud is cloud infrastructure operated solely for a single organization, whether managed internally or by a third party, and hosted either internally or externally. A private cloud refers to cloud computing resources used exclusively by a single business or organization. A private cloud can be physically located on the company’s on-site datacenter. Some companies also pay third-party service providers to host their private cloud. A private cloud is one in which the services and infrastructure are maintained on a private network.
Hybrid cloud is a composition of a public cloud and a private environment, such as a private cloud or on-premise resources, that remain distinct entities but are bound together, offering the benefits of multiple deployment models. Hybrid cloud can also mean the ability to connect collocation, managed and/or dedicated services with cloud resources. Hybrid clouds combine public and private clouds, bound together by technology that allows data and applications to be shared between them. By allowing data and applications to move between private and public clouds, a hybrid cloud gives your business greater flexibility, more deployment options, and helps optimize your existing infrastructure, security, and compliance.
Community Cloud: A community cloud in computing is a collaborative effort in which infrastructure is shared between several organizations from a specific community with common concerns, whether managed internally or by a third-party and hosted internally or externally. This is controlled and used by a group of organizations that have shared interest. The costs are spread over fewer users than a public cloud, so only some of the cost savings potential of cloud computing are realized.
Other AWS Facts and Summaries and Questions/Answers Dump
Definition 1:Amazon DynamoDB is a fully managed proprietary NoSQL database service that supports key-value and document data structures and is offered by Amazon.com as part of the Amazon Web Services portfolio. DynamoDB exposes a similar data model to and derives its name from Dynamo, but has a different underlying implementation. Dynamo had a multi-master design requiring the client to resolve version conflicts and DynamoDB uses synchronous replication across multiple datacenters for high durability and availability.
Definition 2:DynamoDB is a fast and flexible non-relational database service for any scale. DynamoDB enables customers to offload the administrative burdens of operating and scaling distributed databases to AWS so that they don’t have to worry about hardware provisioning, setup and configuration, throughput capacity planning, replication, software patching, or cluster scaling.
Amazon DynamoDB explained
Fully Managed
Fast, consistent Performance
Fine-grained access control
Flexible
Amazon DynamoDB explained
AWS DynamoDB Facts and Summaries
Amazon DynamoDB is a low-latency NoSQL database.
DynamoDB consists of Tables, Items, and Attributes
DynamoDb supports both document and key-value data models
DynamoDB Supported documents formats are JSON, HTML, XML
DynamoDB has 2 types of Primary Keys: Partition Key and combination of Partition Key + Sort Key (Composite Key)
DynamoDB has 2 consistency models: Strongly Consistent / Eventually Consistent
DynamoDB Access is controlled using IAM policies.
DynamoDB has fine grained access control using IAM Condition parameter dynamodb:LeadingKeys to allow users to access only the items where the partition key vakue matches their user ID.
DynamoDB Indexes enable fast queries on specific data columns
DynamoDB indexes give you a different view of your data based on alternative Partition / Sort Keys.
DynamoDB Local Secondary indexes must be created when you create your table, they have same partition Key as your table, and they have a different Sort Key.
DynamoDB Global Secondary Index Can be created at any time: at table creation or after. They have a different partition Key as your table and a different sort key as your table.
A DynamoDB query operation finds items in a table using only the primary Key attribute: You provide the Primary Key name and a distinct value to search for.
A DynamoDB Scan operation examines every item in the table. By default, it return data attributes.
DynamoDB Query operation is generally more efficient than a Scan.
With DynamoDB, you can reduce the impact of a query or scan by setting a smaller page size which uses fewer read operations.
To optimize DynamoDB performance, isolate scan operations to specific tables and segregate them from your mission-critical traffic.
To optimize DynamoDB performance, try Parallel scans rather than the default sequential scan.
To optimize DynamoDB performance: Avoid using scan operations if you can: design tables in a way that you can use Query, Get, or BatchGetItems APIs.
When you scan your table in Amazon DynamoDB, you should follow the DynamoDB best practices for avoiding sudden bursts of read activity.
DynamoDb Provisioned Throughput is measured in Capacity Units.
1 Write Capacity Unit = 1 x 1KB Write per second.
1 Read Capacity Unit = 1 x 4KB Strongly Consistent Read Or 2 x 4KB Eventually Consistent Reads per second. Eventual consistent reads give us the maximum performance with the read operation.
What is the maximum throughput that can be provisioned for a single DynamoDB table?
DynamoDB is designed to scale without limits. However, if you want to exceed throughput rates of 10,000 write capacity units or 10,000 read capacity units for an individual table, you must Contact AWS to increase it.
If you want to provision more than 20,000 write capacity units or 20,000 read capacity units from a single subscriber account, you must first contact AWS to request a limit increase.
Dynamo Db Performance: DAX is a DynamoDB-compatible caching service that enables you to benefit from fast in-memory performance for demanding applications.
As an in-memory cache, DAX reduces the response times of eventually-consistent read workloads by an order of magnitude, from single-digit milliseconds to microseconds
DAX improves response times for Eventually Consistent reads only.
With DAX, you point your API calls to the DAX cluster instead of your table.
If the item you are querying is on the cache, DAX will return it; otherwise, it will perform and Eventually Consistent GetItem operation to your DynamoDB table.
DAX reduces operational and application complexity by providing a managed service that is API compatible with Amazon DynamoDB, and thus requires only minimal functional changes to use with an existing application.
DAX is not suitable for write-intensive applications or applications that require Strongly Consistent reads.
For read-heavy or bursty workloads, DAX provides increased throughput and potential operational cost savings by reducing the need to over-provision read capacity units. This is especially beneficial for applications that require repeated reads for individual keys.
Dynamo Db Performance: ElastiCache
In-memory cache sits between your application and database
2 different caching strategies: Lazy loading and Write Through: Lazy loading only caches the data when it is requested
Elasticache Node failures are not fatal, just lots of cache misses
Avoid stale data by implementing a TTL.
Write-Through strategy writes data into cache whenever there is a change to the database. Data is never stale
Write-Through penalty: Each write involves a write to the cache. Elasticache node failure means that data is missing until added or updated in the database.
Elasticache is wasted resources if most of the data is never used.
Time To Live (TTL) for DynamoDB allows you to define when items in a table expire so that they can be automatically deleted from the database. TTL is provided at no extra cost as a way to reduce storage usage and reduce the cost of storing irrelevant data without using provisioned throughput. With TTL enabled on a table, you can set a timestamp for deletion on a per-item basis, allowing you to limit storage usage to only those records that are relevant.
DynamoDB Security: DynamoDB uses the CMK to generate and encrypt a unique data key for the table, known as the table key. With DynamoDB, AWS Owned, or AWS Managed CMK can be used to generate & encrypt keys. AWS Owned CMK is free of charge while AWS Managed CMK is chargeable. Customer managed CMK’s are not supported with encryption at rest.
Amazon DynamoDB offers fully managed encryption at rest. DynamoDB encryption at rest provides enhanced security by encrypting your data at rest using an AWS Key Management Service (AWS KMS) managed encryption key for DynamoDB. This functionality eliminates the operational burden and complexity involved in protecting sensitive data.
DynamoDB is a alternative solution which can be used for storage of session management. The latency of access to data is less , hence this can be used as a data store for session management
DynamoDB Streams Use Cases and Design Patterns:
How do you set up a relationship across multiple tables in which, based on the value of an item from one table, you update the item in a second table?
How do you trigger an event based on a particular transaction?
How do you audit or archive transactions?
How do you replicate data across multiple tables (similar to that of materialized views/streams/replication in relational data stores)?
As a NoSQL database, DynamoDB is not designed to support transactions. Although client-side libraries are available to mimic the transaction capabilities, they are not scalable and cost-effective. For example, the Java Transaction Library for DynamoDB creates 7N+4 additional writes for every write operation. This is partly because the library holds metadata to manage the transactions to ensure that it’s consistent and can be rolled back before commit.
You can use DynamoDB Streams to address all these use cases. DynamoDB Streams is a powerful service that you can combine with other AWS services to solve many similar problems. When enabled, DynamoDB Streams captures a time-ordered sequence of item-level modifications in a DynamoDB table and durably stores the information for up to 24 hours. Applications can access a series of stream records, which contain an item change, from a DynamoDB stream in near real time.
AWS maintains separate endpoints for DynamoDB and DynamoDB Streams. To work with database tables and indexes, your application must access a DynamoDB endpoint. To read and process DynamoDB Streams records, your application must access a DynamoDB Streams endpoint in the same Region
20 global secondary indexes are allowed per table? (by default)
What is one key difference between a global secondary index and a local secondary index? A local secondary index must have the same partition key as the main table
How many tables can an AWS account have per region? 256
How many secondary indexes (global and local combined) are allowed per table? (by default): 25 You can define up to 5 local secondary indexes and 20 global secondary indexes per table (by default) – for a total of 25.
How can you increase your DynamoDB table limit in a region? By contacting AWS and requesting a limit increase
For any AWS account, there is an initial limit of 256 tables per region.
The minimum length of a partition key value is 1 byte. The maximum length is 2048 bytes.
The minimum length of a sort key value is 1 byte. The maximum length is 1024 bytes.
For tables with local secondary indexes, there is a 10 GB size limit per partition key value. A table with local secondary indexes can store any number of items, as long as the total size for any one partition key value does not exceed 10 GB.
The following diagram shows a local secondary index named LastPostIndex. Note that the partition key is the same as that of the Thread table, but the sort key is LastPostDateTime. AWS DynamoDB secondary indexes example
Relational vs Non Relational (SQL vs NoSQL)
Relational vs Non RelationalSQL vs NOSQLSQL vs NoSQL in AWS
Q0: What should the Developer enable on the DynamoDB table to optimize performance and minimize costs?
A. Amazon DynamoDB auto scaling
B. Amazon DynamoDB cross-region replication
C. Amazon DynamoDB Streams
D. Amazon DynamoDB Accelerator
D. DAX is a DynamoDB-compatible caching service that enables you to benefit from fast in-memory performance for demanding applications. DAX addresses three core scenarios:
As an in-memory cache, DAX reduces the response times of eventually-consistent read workloads by an order of magnitude, from single-digit milliseconds to microseconds.
DAX reduces operational and application complexity by providing a managed service that is API-compatible with Amazon DynamoDB, and thus requires only minimal functional changes to use with an existing application.
For read-heavy or bursty workloads, DAX provides increased throughput and potential operational cost savings by reducing the need to over-provision read capacity units. This is especially beneficial for applications that require repeated reads for individual keys.
Q2: A security system monitors 600 cameras, saving image metadata every 1 minute to an Amazon DynamoDb table. Each sample involves 1kb of data, and the data writes are evenly distributed over time. How much write throughput is required for the target table?
A. 6000
B. 10
C. 3600
D. 600
B. When you mention the write capacity of a table in Dynamo DB, you mention it as the number of 1KB writes per second. So in the above question, since the write is happening every minute, we need to divide the value of 600 by 60, to get the number of KB writes per second. This gives a value of 10.
You can specify the Write capacity in the Capacity tab of the DynamoDB table.
Q3: You are developing an application that will interact with a DynamoDB table. The table is going to take in a lot of read and write operations. Which of the following would be the ideal partition key for the DynamoDB table to ensure ideal performance?
A. CustomerID
B. CustomerName
C. Location
D. Age
Answer- A
Use high-cardinality attributes. These are attributes that have distinct values for each item, like e-mailid, employee_no, customerid, sessionid, orderid, and so on..
Use composite attributes. Try to combine more than one attribute to form a unique key.
Reference: Choosing the right DynamoDB Partition Key
Q4: A DynamoDB table is set with a Read Throughput capacity of 5 RCU. Which of the following read configuration will provide us the maximum read throughput?
A. Read capacity set to 5 for 4KB reads of data at strong consistency
B. Read capacity set to 5 for 4KB reads of data at eventual consistency
C. Read capacity set to 15 for 1KB reads of data at strong consistency
D. Read capacity set to 5 for 1KB reads of data at eventual consistency
Answer: B.
The calculation of throughput capacity for option B would be:
Read capacity(5) * Amount of data(4) = 20.
Since its required at eventual consistency , we can double the read throughput to 20*2=40
Q5: Your team is developing a solution that will make use of DynamoDB tables. Due to the nature of the application, the data is needed across a couple of regions across the world. Which of the following would help reduce the latency of requests to DynamoDB from different regions?
A. Enable Multi-AZ for the DynamoDB table
B. Enable global tables for DynamoDB
C. Enable Indexes for the table
D. Increase the read and write throughput for the tablez
Answer: B
Amazon DynamoDB global tables provide a fully managed solution for deploying a multi-region, multimaster database, without having to build and maintain your own replication solution. When you create a global table, you specify the AWS regions where you want the table to be available. DynamoDB performs all of the necessary tasks to create identical tables in these regions, and propagate ongoing data changes to all of them.
Reference: Global Tables
Q6: An application is currently accessing a DynamoDB table. Currently the tables queries are performing well. Changes have been made to the application and now the performance of the application is starting to degrade. After looking at the changes , you see that the queries are making use of an attribute which is not the partition key? Which of the following would be the adequate change to make to resolve the issue?
A. Add an index for the DynamoDB table
B. Change all the queries to ensure they use the partition key
C. Enable global tables for DynamoDB
D. Change the read capacity on the table
Answer: A
Amazon DynamoDB provides fast access to items in a table by specifying primary key values. However, many applications might benefit from having one or more secondary (or alternate) keys available, to allow efficient access to data with attributes other than the primary key. To address this, you can create one or more secondary indexes on a table, and issue Query or Scan requests against these indexes.
A secondary index is a data structure that contains a subset of attributes from a table, along with an alternate key to support Query operations. You can retrieve data from the index using a Query, in much the same way as you use Query with a table. A table can have multiple secondary indexes, which gives your applications access to many different query patterns.
Q7: Company B has created an e-commerce site using DynamoDB and is designing a products table that includes items purchased and the users who purchased the item.
When creating a primary key on a table which of the following would be the best attribute for the partition key? Select the BEST possible answer.
A. None of these are correct.
B. user_id where there are many users to few products
C. category_id where there are few categories to many products
D. product_id where there are few products to many users
Answer: B.
When designing tables it is important for the data to be distributed evenly across the entire table. It is best practice for performance to set your primary key where there are many primary keys to few rows. An example would be many users to few products. An example of bad design would be a primary key of product_id where there are few products but many users.
When designing tables it is important for the data to be distributed evenly across the entire table. It is best practice for performance to set your primary key where there are many primary keys to few rows. An example would be many users to few products. An example of bad design would be a primary key of product_id where there are few products but many users.
Reference: Partition Keys and Sort Keys
Q8: Which API call can be used to retrieve up to 100 items at a time or 16 MB of data from a DynamoDB table?
A. BatchItem
B. GetItem
C. BatchGetItem
D. ChunkGetItem
Answer: C. BatchGetItem
The BatchGetItem operation returns the attributes of one or more items from one or more tables. You identify requested items by primary key.
A single operation can retrieve up to 16 MB of data, which can contain as many as 100 items. BatchGetItem will return a partial result if the response size limit is exceeded, the table's provisioned throughput is exceeded, or an internal processing failure occurs. If a partial result is returned, the operation returns a value for UnprocessedKeys. You can use this value to retry the operation starting with the next item to get.Reference: API-Specific Limits
Q9: Which DynamoDB limits can be raised by contacting AWS support?
A. The number of hash keys per account
B. The maximum storage used per account
C. The number of tables per account
D. The number of local secondary indexes per account
E. The number of provisioned throughput units per account
Answer: C. and E.
For any AWS account, there is an initial limit of 256 tables per region.
AWS places some default limits on the throughput you can provision.
These are the limits unless you request a higher amount.
To request a service limit increase see https://aws.amazon.com/support.
Q10: Which approach below provides the least impact to provisioned throughput on the “Product”
table?
A. Create an “Images” DynamoDB table to store the Image with a foreign key constraint to
the “Product” table
B. Add an image data type to the “Product” table to store the images in binary format
C. Serialize the image and store it in multiple DynamoDB tables
D. Store the images in Amazon S3 and add an S3 URL pointer to the “Product” table item
for each image
Answer: D.
Amazon DynamoDB currently limits the size of each item that you store in a table (see Limits in DynamoDB). If your application needs to store more data in an item than the DynamoDB size limit permits, you can try compressing one or more large attributes, or you can store them as an object in Amazon Simple Storage Service (Amazon S3) and store the Amazon S3 object identifier in your DynamoDB item.
Compressing large attribute values can let them fit within item limits in DynamoDB and reduce your storage costs. Compression algorithms such as GZIP or LZO produce binary output that you can then store in a Binary attribute type.
Reference: Best Practices for Storing Large Items and Attributes
Q11: You’re creating a forum DynamoDB database for hosting forums. Your “thread” table contains the forum name and each “forum name” can have one or more “subjects”. What primary key type would you give the thread table in order to allow more than one subject to be tied to the forum primary key name?
A. Hash
B. Range and Hash
C. Primary and Range
D. Hash and Range
Answer: D.
Each forum name can have one or more subjects. In this case, ForumName is the hash attribute and Subject is the range attribute.
Definition 1: Amazon S3 or Amazon Simple Storage Service is a “simple storage service” offered by Amazon Web Services that provides object storage through a web service interface. Amazon S3 uses the same scalable storage infrastructure that Amazon.com uses to run its global e-commerce network.
Definition 2: Amazon Simple Storage Service (Amazon S3) is an object storage service that offers industry-leading scalability, data availability, security, and performance.
AWS S3 Explained graphically:
Amazon S3 Explained
Amazon S3 Explained in picturesAmazon S3 Explained graphically
AWS S3 Facts and summaries
S3 is a universal namespace, meaning each S3 bucket you create must have a unique name that is not being used by anyone else in the world.
S3 is object based: i.e allows you to upload files.
Files can be from 0 Bytes to 5 TB
What is the maximum length, in bytes, of a DynamoDB range primary key attribute value?
The maximum length of a DynamoDB range primary key attribute value is 2048 bytes (NOT 256 bytes).
S3 has unlimited storage.
Files are stored in Buckets.
Read after write consistency for PUTS of new Objects
Eventual Consistency for overwrite PUTS and DELETES (can take some time to propagate)
S3 Standard (durable, immediately available, frequently accesses)
Amazon S3 Intelligent-Tiering (S3 Intelligent-Tiering): It works by storing objects in two access tiers: one tier that is optimized for frequent access and another lower-cost tier that is optimized for infrequent access.
S3 – One Zone-Infrequent Access – S3 One Zone IA: Same ad IA. However, data is stored in a single Availability Zone only
S3 – Reduced Redundancy Storage (data that is easily reproducible, such as thumbnails, etc.)
Glacier – Archived data, where you can wait 3-5 hours before accessing
You can have a bucket that has different objects stored in S3 Standard, S3 Intelligent-Tiering, S3 Standard-IA, and S3 One Zone-IA.
The default URL for S3 hosted websites lists the bucket name first followed by s3-website-region.amazonaws.com . Example: enoumen.com.s3-website-us-east-1.amazonaws.com
Core fundamentals of an S3 object
Key (name)
Value (data)
Version (ID)
Metadata
Sub-resources (used to manage bucket-specific configuration)
Bucket Policies, ACLs,
CORS
Transfer Acceleration
Object-based storage only for files
Not suitable to install OS on.
Successful uploads will generate a HTTP 200 status code.
S3 Security – Summary
By default, all newly created buckets are PRIVATE.
You can set up access control to your buckets using:
Bucket Policies – Applied at the bucket level
Access Control Lists – Applied at an object level.
S3 buckets can be configured to create access logs, which log all requests made to the S3 bucket. These logs can be written to another bucket.
S3 Encryption
Encryption In-Transit (SSL/TLS)
Encryption At Rest:
Server side Encryption (SSE-S3, SSE-KMS, SSE-C)
Client Side Encryption
Remember that we can use a Bucket policy to prevent unencrypted files from being uploaded by creating a policy which only allows requests which include the x-amz-server-side-encryption parameter in the request header.
S3 CORS (Cross Origin Resource Sharing):
CORS defines a way for client web applications that are loaded in one domain to interact with resources in a different domain.
Used to enable cross origin access for your AWS resources, e.g. S3 hosted website accessing javascript or image files located in another bucket. By default, resources in one bucket cannot access resources located in another. To allow this we need to configure CORS on the bucket being accessed and enable access for the origin (bucket) attempting to access.
Always use the S3 website URL, not the regular bucket URL. E.g.: https://s3-eu-west-2.amazonaws.com/acloudguru
S3 CloudFront:
Edge locations are not just READ only – you can WRITE to them too (i.e put an object on to them.)
Objects are cached for the life of the TTL (Time to Live)
You can clear cached objects, but you will be charged. (Invalidation)
S3 Performance optimization – 2 main approaches to Performance Optimization for S3:
GET-Intensive Workloads – Use Cloudfront
Mixed Workload – Avoid sequencial key names for your S3 objects. Instead, add a random prefix like a hex hash to the key name to prevent multiple objects from being stored on the same partition.
The best way to handle large objects uploads to the S3 service is to use the Multipart upload API. The Multipart upload API enables you to upload large objects in parts.
You can enable versioning on a bucket, even if that bucket already has objects in it. The already existing objects, though, will show their versions as null. All new objects will have version IDs.
Bucket names cannot start with a . or – characters. S3 bucket names can contain both the . and – characters. There can only be one . or one – between labels. E.G mybucket-com mybucket.com are valid names but mybucket–com and mybucket..com are not valid bucket names.
What is the maximum number of S3 buckets allowed per AWS account (by default)? 100
You successfully upload an item to the us-east-1 region. You then immediately make another API call and attempt to read the object. What will happen? All AWS regions now have read-after-write consistency for PUT operations of new objects. Read-after-write consistency allows you to retrieve objects immediately after creation in Amazon S3. Other actions still follow the eventual consistency model (where you will sometimes get stale results if you have recently made changes)
S3 bucket policies require a Principal be defined. Review the access policy elements here
What checksums does Amazon S3 employ to detect data corruption?
Amazon S3 uses a combination of Content-MD5 checksums and cyclic redundancy checks (CRCs) to detect data corruption. Amazon S3 performs these checksums on data at rest and repairs any corruption using redundant data. In addition, the service calculates checksums on all network traffic to detect corruption of data packets when storing or retrieving data.
Q0: You’ve written an application that uploads objects onto an S3 bucket. The size of the object varies between 200 – 500 MB. You’ve seen that the application sometimes takes a longer than expected time to upload the object. You want to improve the performance of the application. Which of the following would you consider?
A. Create multiple threads and upload the objects in the multiple threads
B. Write the items in batches for better performance
C. Use the Multipart upload API
D. Enable versioning on the Bucket
C. All other options are invalid since the best way to handle large object uploads to the S3 service is to use the Multipart upload API. The Multipart upload API enables you to upload large objects in parts. You can use this API to upload new large objects or make a copy of an existing object. Multipart uploading is a three-step process: You initiate the upload, you upload the object parts, and after you have uploaded all the parts, you complete the multipart upload. Upon receiving the complete multipart upload request, Amazon S3 constructs the object from the uploaded parts, and you can then access the object just as you would any other object in your bucket.
Q2: You are using AWS SAM templates to deploy a serverless application. Which of the following resource will embed application from Amazon S3 buckets?
A. AWS::Serverless::Api
B. AWS::Serverless::Application
C. AWS::Serverless::Layerversion
D. AWS::Serverless::Function
Answer – B
AWS::Serverless::Application resource in AWS SAm template is used to embed application frm Amazon S3 buckets.
Reference: Declaring Serverless Resources
Q3: A static web site has been hosted on a bucket and is now being accessed by users. One of the web pages javascript section has been changed to access data which is hosted in another S3 bucket. Now that same web page is no longer loading in the browser. Which of the following can help alleviate the error?
A. Enable versioning for the underlying S3 bucket.
B. Enable Replication so that the objects get replicated to the other bucket
C. Enable CORS for the bucket
D. Change the Bucket policy for the bucket to allow access from the other bucket
Answer – C
Cross-origin resource sharing (CORS) defines a way for client web applications that are loaded in one domain to interact with resources in a different domain. With CORS support, you can build rich client-side web applications with Amazon S3 and selectively allow cross-origin access to your Amazon S3 resources.
Cross-Origin Resource Sharing: Use-case Scenarios The following are example scenarios for using CORS:
Scenario 1: Suppose that you are hosting a website in an Amazon S3 bucket named website as described in Hosting a Static Website on Amazon S3. Your users load the website endpoint http://website.s3-website-us-east-1.amazonaws.com. Now you want to use JavaScript on the webpages that are stored in this bucket to be able to make authenticated GET and PUT requests against the same bucket by using the Amazon S3 API endpoint for the bucket, website.s3.amazonaws.com. A browser would normally block JavaScript from allowing those requests, but with CORS you can congure your bucket to explicitly enable cross-origin requests from website.s3-website-us-east-1.amazonaws.com.
Scenario 2: Suppose that you want to host a web font from your S3 bucket. Again, browsers require a CORS check (also called a preight check) for loading web fonts. You would congure the bucket that is hosting the web font to allow any origin to make these requests.
Q4: Your mobile application includes a photo-sharing service that is expecting tens of thousands of users at launch. You will leverage Amazon Simple Storage Service (S3) for storage of the user Images, and you must decide how to authenticate and authorize your users for access to these images. You also need to manage the storage of these images. Which two of the following approaches should you use? Choose two answers from the options below
A. Create an Amazon S3 bucket per user, and use your application to generate the S3 URL for the appropriate content.
B. Use AWS Identity and Access Management (IAM) user accounts as your application-level user database, and offload the burden of authentication from your application code.
C. Authenticate your users at the application level, and use AWS Security Token Service (STS)to grant token-based authorization to S3 objects.
D. Authenticate your users at the application level, and send an SMS token message to the user. Create an Amazon S3 bucket with the same name as the SMS message token, and move the user’s objects to that bucket.
Answer- C
The AWS Security Token Service (STS) is a web service that enables you to request temporary, limited-privilege credentials for AWS Identity and Access Management (IAM) users or for users that you authenticate (federated users). The token can then be used to grant access to the objects in S3.
You can then provides access to the objects based on the key values generated via the user id.
Q5: Both ACLs and Bucket Policies can be used to grant access to S3 buckets. Which of the following statements is true about ACLs and Bucket policies?
A. Bucket Policies are Written in JSON and ACLs are written in XML
B. ACLs can be attached to S3 objects or S3 Buckets
C. Bucket Policies and ACLs are written in JSON
D. Bucket policies are only attached to s3 buckets, ACLs are only attached to s3 objects
Answer: A. and B.
Only Bucket Policies are written in JSON, ACLs are written in XML.
While Bucket policies are indeed only attached to S3 buckets, ACLs can be attached to S3 Buckets OR S3 Objects.
Reference:
Q6: What are good options to improve S3 performance when you have significantly high numbers of GET requests?
A. Introduce random prefixes to S3 objects
B. Introduce random suffixes to S3 objects
C. Setup CloudFront for S3 objects
D. Migrate commonly used objects to Amazon Glacier
Answer: C
CloudFront caching is an excellent way to avoid putting extra strain on the S3 service and to improve the response times of reqeusts by caching data closer to users at CloudFront locations.
S3 Transfer Acceleration optimizes the TCP protocol and adds additional intelligence between the client and the S3 bucket, making S3 Transfer Acceleration a better choice if a higher throughput is desired. If you have objects that are smaller than 1GB or if the data set is less than 1GB in size, you should consider using Amazon CloudFront's PUT/POST commands for optimal performance.
Reference: Amazon S3 Transfer Acceleration
Q7: If an application is storing hourly log files from thousands of instances from a high traffic
web site, which naming scheme would give optimal performance on S3?
A. Sequential
B. HH-DD-MM-YYYY-log_instanceID
C. YYYY-MM-DD-HH-log_instanceID
D. instanceID_log-HH-DD-MM-YYYY
E. instanceID_log-YYYY-MM-DD-HH
Answer: A. B. C. D. and E.
Amazon S3 now provides increased performance to support at least 3,500 requests per second to add data and 5,500 requests per second to retrieve data, which can save significant processing time for no additional charge. Each S3 prefix can support these request rates, making it simple to increase performance significantly.
This S3 request rate performance increase removes any previous guidance to randomize object prefixes to achieve faster performance. That means you can now use logical or sequential naming patterns in S3 object naming without any performance implications.
Q9: You created three S3 buckets – “mywebsite.com”, “downloads.mywebsite.com”, and “www.mywebsite.com”. You uploaded your files and enabled static website hosting. You specified both of the default documents under the “enable static website hosting” header. You also set the “Make Public” permission for the objects in each of the three buckets. You create the Route 53 Aliases for the three buckets. You are going to have your end users test your websites by browsing to http://mydomain.com/error.html, http://downloads.mydomain.com/index.html, and http://www.mydomain.com. What problems will your testers encounter?
A. http://mydomain.com/error.html will not work because you did not set a value for the error.html file
B. There will be no problems, all three sites should work.
C. http://www.mywebsite.com will not work because the URL does not include a file name at the end of it.
D. http://downloads.mywebsite.com/index.html will not work because the “downloads” prefix is not a supported prefix for S3 websites using Route 53 aliases
Answer: B.
It used to be that the only allowed domain prefix when creating Route 53 Aliases for S3 static websites was the “www” prefix. However, this is no longer the case. You can now use other subdomain.
AWS Certification Exams Roadmap[/caption]
