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You can delete AWS Organization in an account through the CLI command below: aws organizations delete-organization --profile a2 As we have the organization deleted, you would see no organization while navigating to the AWS Organization home page. Create an organization. aws organizations create-organization --profile a2 We're not passing anything like name. That means, you can create at most only one organization in an account. Let's go back to the console. That created an Organization. It contains a Root OU and a member account (current account which is the management account). Each organization has a management account where the features of the organization are configured. In our case, a2 is the management account as we have created the organization in a2 account (current account). Root is the top most OU (Organizational Unit). An OU, which is a logical grouping of accounts or other OUs, can have either another OU or an account as its child. An OU can have more than one chil...

When encountering the phrase "handle peak load traffic" in a question, think of AWS Auto-Scaling.

Use a Type A Record without an Alias for EC2 instances. Use a Type A Record with an Alias for ELB, CloudFront, and S3. Use a CNAME Record with no Alias for RDS.

How to handle peak load of application? - When encountering the phrase "handle peak load traffic" in a question, think of AWS Auto-Scaling. - Use Auto-Scaling with Spot instances  - Use Auto-Scaling with On-Demand instances  What to be used for steady state load of application? - Use Reserved instances What EC2 pricing model should be used for RDS? - Use Reserved instances for RDS Which Route53 record should be used for EC2? - Use a Type A Record without an Alias for EC2 instances Which Route53 record should be used for ELB, CloudFront, S3? - Use a Type A Record with an Alias for ELB, CloudFront, and S3 Which Route53 record should be used for RDS? - Use a CNAME Record with no Alias for RDS Which service should be used to discover and protect sensitive data in AWS using machine-learning and pattern-matching? - Using Amazon Macie Which AWS service should be used to scan Amazon S3 buckets for data security and data privacy? - Using Amazon Macie Where to store encryption keys? - ...

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The ALB spans all subnets in a VPC i.e., it is not inside a subnet but VPC. ALB is bound to Target Groups (TGs). TGs are bound to subnets.

The user requests to get static contents served from CloudFront are directed to the nearby Edge locations .

RDS DB, in one AZ, replicates data synchronously to Standby Replica (created automatically), in another AZ, in Multi-AZ deployment. RDS DB replicates data asynchronously to Read Replicas .

If the objects from the source bucket in the same region are replicated to another bucket in the same region, it is called same region replication (SRR). If the objects are replicated to a bucket in a different region, it is called cross region replication (CRR). 

Use ASG if the EC2 is unable to handle surge of requests. ASG can be integrated with SQS. Based on the length of the queue, the group of EC2 instances can be increased or decreased. 

Application Load Balancer (ALB) Auto Scaling Group (ASG) CloudFront Relational Database Service (RDS) Simple Storage Service (S3) NAT Gateway & NAT Instance

If I have an MSSQL server on-premises and I want to migrate that in AWS cloud (as MSSQL server itself), this is called a homogeneous database migration. If I have an MSSQL server on-premises and I want to transform and migrate that to a PostgreSQL database in AWS cloud, this is called a heterogeneous database migration. In this case the schema of the source and target database would be different (and also the datatypes, DB codes as the DB engines are different). So, you have to use a tool called SCT (schema conversion tool) to convert the source schema to the target schema (and also code transformation). After this, the DMS (database migration service) can be used to migrate the on-promises database into the AWS cloud (to RDS/EC2). The major advantage of using DMS service is, the source database would be fully operational while migrating the database. DMS can also move data between SQL, NoSQL and text-based targets.

Use ELB target group health check if the health check endpoint is a simple HTML webpage. Use Route 53 health check if the health check endpoint makes a database query. This is because the Route 53 health check has an overall lower request count compared to the Target Group health check.

You can use AWS ChatBot to receive the SNS notifications and, from there, you can forward the notifications to a messaging application like Slack.

Successful code ranges - 200 or 300 Unsuccessful code ranges - 400 or 500

It monitors endpoints by sending HTTP requests at regular intervals. It marks the endpoint 'healthy' if the response is successful, 'unhealthy' otherwise. The endpoint will be marked 'unhealthy' if there is no response. In addition to endpoints, the Route 53 health checks can also be used to monitor other calculated health checks or cloudwatch alarms' state. Question: what is monitoring other health checks? You might want to make sure some minimum number of resources among multiple web servers are healthy. Question: What does monitoring a cloudwatch alarm mean? You could have created a CloudWatch alarm that monitors the number of targets running healthy in the load balancer's target group. The Route 53 health check could monitor such CloudWatch alarms. You can specify the endpoint using an IP address or domain name (the domain name could be configured in Route 53).  Example: The endpoint can be from an API Gateway which has a path parameter using which i...

Suppose you have a database and it has got a products table. And, there are 100 users. 60 users are reading data of product A and the remaining 40 users are reading data of product B. You can do either one of the following: 1. You can create an elasticache cluster. Let the first among 60 users query product A and the remaining 59 users use the data from the cache. ElastiCache is effective in caching frequent requests. 2. Create read replicas to distribute the read-only traffic across multiple database instances this improving the read performance.

Cloudwatch monitors two things: 1. Your AWS resources 2. The applications running on your AWS resources There is something called cloudwatch log agent which you can install on your machine on premises. This can send application logs to cloudwatch logs. You can filter these logs using cloudwatch metric filter. For example, you can filter only the out of memory exception and find the total count of it. These metric filters are monitored by cloudwatch alarms. And then you can notify others using SNS.

You have few AWS resources. You want to compare their current configurations with expected/desired configurations. This can be achieved through an AWS service called AWS Config. It asses, audit and evaluate the configurations of AWS resources.