AWS Fundamentals

 AWS SQS AWS SQS -  Used to asychronously decouple application  Suppports multiple producers and consumers  The consumer polls the queue for messages. Once a consumer processes a messages, it deletes it from the queue using DeleteMessage API Unlimited number of messages in queue Max 10 messages recieved per batch (configured using MaxNumberOfMessages parameter in the ReceiveMessage API) Max message size - 256kb  Consumers could be EC2 instances or Lamda function SQS cannot ingest data, it must be sent to the queue by the producer (use kinesis - kinesis data stream kds instead) Queue Types -  Standard queue -  Unlimited throughput (publish any number of message per second into the queue) Low latency (<10 ms on publish and recieve) Can have duplicate messages (at least once delivery) Can have out of order messages (best effort ording) Fifo queue - Limited throughput -  300 msg/s without batching (batch size=1) 3000 msg/s withour batching (batch s...

 AWS Config AWS Config -  Regional service Can aggregated across regions and accounts Record Configuration changes over time Evaluate compliance of resources using config rules Does not prevent non-complaint actions from happening  Evaluate config rules -  For each config changes  At regular time intervals Can make custom config rules (must be define in lamda function) such as -  Check if EBS disk is of type gp2  Check if each Ec2 instance is t2.micro Can be used along with CloudTrail to get timeline of changes in configuration and complaince overtime Integrates with EventBridge or SNS to trigger notifications when AWS resources are non-compliant Remediation -    Automate remediation of non-compliant resources using SSM automation documents  You can set remediation retries if the resource is still non-complaint For Ex- If IAm access keys expires (non-compliant), trigger an auto-remediation action to revoke unused IAM user credentials...

 AWS CloudTrail AWS CloudTrail -  AWS CloudTrail is a web service that records activity made on your account  A cloudtrail trail can be treated which delivers log files to an S3 bucket CloutTrail is about logging and saves a history of API calls for your AWS account Provides governance, compliance, and operational and auditing of your AWS account  Enabled by default Records the API calls made within the AWS account  Event Retention- 90days CloudTrail logs up to the last 90 days can be analyzed in Cloudtrail console. Older logs should be present in S3 and can be analyzed using athena modification to logs files can be Detected by enabling Log File Validation on the logging bucket  Event Types -  Managment Events -  Events of operation that modifies AWS resources like creating IAM user, deleting subnet  Enabled by default  Can saperate read events from write events  Data Events -  Events of operation that modify data like Lamda fu...

 AWS CloudWatch AWS CloudWatch -  AWS CloudWatch is a monitoring service for AWS cloud resources and the application you run on AWS CloudWatch is is to collect and track metrics, collect and monitor log files, and set alarms CloudWatch alarms monitor metrics and can be configured to automatically initiate actions CloudWatch logs centralizes logs from systems, applications, and AWS Services CloudWatch events delivers a stream of system events that describe and changes in AWS resources CloudWatch is serverless performance monitoring service  CloudWatch integrates with AWS IAM Metrics -  Metrics are the fundamental concept in CloudWatch  A metrics represents a time-ordered set of data points that are published  Up to 30 dimensions per metrics Dimension in an attribute to the metrics Metrics exist within a region Metrics cannot be deleted but automatically expire after 15 months Custom Metrics -  You can publish your own metrics to CloudWatch using the AWS...

 AWS API Gateway AWS API Gateway -  Enables developers to create, publish, maintain, monitoring, and secure APIs at any scale Allows creating, deploying and managing a restful api to to expose backend HTTP endpoints, lamda functions or other AWS services  Together with lamda, API Gateway forms the app facing part of the AWS Serverless Infrastructure Features -  API Gateway can execute Lamda code in your account,start step function state machines, or make calls to elastic beanstalk, EC2, or web services outside of AWS with publically acceessible HTTP endpoints  API Gateway helps you define plans that meter and restric third party developer access to your API  API Gateway helps you to manage traffic to your backend systems by allowing you to set throttling rules based on the number of requests per sec for each HTTP method in your API  You can set up a cache with a customaizable keys and time-to-live in sec for your API data to avoid hitting your backend ...

 AWS Lambda AWS Lambda - AWS Lamda let you run a code as functions without provisioning or managing servers Lamda based applications are composed of functions triggered by events With serverless computing your application still run on servers but all the server management is done by AWS You cannot log into compute instances that run lamda function or customize the operating system or language runtime Features of AWS Lamda -  Auto Scaling and High Availability -  AWS lamda will make sure that your application was highly available to the end users when there is sudden incoming traffic. Highly available can be achieved by scaling the application  Serverless Execution - there is no need for provisioning the servers manually in AWS. AWS will lamda will provision the underlying infrastructure based on the triggers you are mentioned whenevr a new file is uploaded to a particular then AWS lamda will automatically trigger and takes care of the infastructure Pay-Per-Use-Pricin...

 AWS Global Accelerator AWS Global Accelerator -  AWS Global Accelerator is service that improves availability and performance of application with local or global users It provides a static IP addresses that act as fix entry point to appication end points in single or multiple AWS regions such as  ALB, NLB or EC2 Uses the AWS Global Network to optimize the path from users to application, improving the performance of TCP and UDP traffic AWS GA continuously monitor the health of the application endpoints and will detect an unhealthy endpoint and redirect the traffic to healthy endpoint within 1min  Benefits and Details of AWS GA -  Uses Redundant (two) static anycast IP  addresses in different network zones The redundant pair are globally advertised Uses AWS Edge Location - addresses are announced from multiple edge location at the same time Addresses are regional AWS resources or endpoints AWS GAs IP addresses serve as the frontend interface of applications ...