AWS Blog

AWS supported CIDR block range

VPC Limits

Private vs Public IP (IPV4) Fundamental Differences

Public IP:

1. Public IP means the machine can be identified on the internet (WWW)

2. Must be unique across the whole web (not two machines can have the same public IP).

3. Can be geo-located easily

Private IP:

1. Private IP means the machine can only be identified on a private network only

2. The IP must be unique across the private network

3. BUT two different private networks (two companies) can have the same IPs.

4. Machines connect to WWW using an internet gateway (a proxy)

5. Only a specified range of IPs can be used as private IP

Why use a custom AMI?

1. Pre-installed packages needed

2. Faster boot time (no need for ec2 user data at boot time)

3. Machine comes configured with monitoring / enterprise software

4. Security concerns - control over the machines in the network

5. Control of maintenance and updates of AMIs over time

6. Active Directory Integration out of the box

7. Installing your app ahead of time (for faster denloys when auto-scaling)

8. Using someone else's AMI that is optimised for DB, etc...

AMI Storage

• Your AMI take space and they live in Amazon S3 • Amazon S3 is a durable, cheap and resilient storage where most of your backups will live (but you won't see in the S3 console) • By default, your AMls are private, and locked for your account / region. • You can also make your own AMI or tranfer to ther AWS accounts or sell them on the Marketplace.

Security Groups

• Can be attached to multible instances. • Locked down to a region / VPC combination. • Does live "outside" the EC2 - if traffic is blocked the EC2 instance won't see it. • If your application is not accessible (time out), then it's a security group issue. • If your application gives a "connection refused" error, then it's an application error or it's not launched. • All inbound traffic is blocked by default

Elastic IP

• With an Elastic IP address, you can mask the failure of an instance or software by rapidly remapping the address to another instance in your account. • You can only have 5 Elastic IP in your account (you can ask AWS to increase that).

Types of Placement Groups:

1. Cluster Group: Same Rack, Same AZs. Packs instances close together inside an Availability Zone. This strategy enables workloads to achieve the low-latency network performance necessary for tightly-coupled node-to-node communication that is typical of HPC applications.

2. Spread Group: Small group of instances across multiple AZs. Strictly places a small group of instances across distinct underlying hardware to reduce correlated failures.

3. Partition Group: Combination of the above. Spreads your instances across logical partitions such that groups of instances in one partition do not share the underlying hardware with groups of instances in different partitions. This strategy is typically used by large distributed and replicated workloads, such as Hadoop, Cassandra, and Kafka.

ALB vs NLB vs CLB

• Web applications with L7 routing (HTTP/HTTPS)

• Microservices architectures (e.g. Docker containers)

• Lambda targets

• TCP and UDP based applications

• Ultra-low latency

• Static IP addresses

• Load balance virtual appliances such as:

1. Intrusion detection systems (IDS)

2. Intrusion prevention systems (IPS)

3. Next generation firewalls (NGFW)

4. Web application firewalls (WAF)

5. Distributed denial of service protection systems (DDoS)

• Integrate with Auto Scaling groups for elasticity

• Apply network monitoring and logging for analytics

S3

Versioning Objects in S3

• Cannot Be Disabled: Once enabled, versioning cannot be disabled; it can only be suspended temporarily if needed.

• All Versions: All versions of an object are stored in S3, including all writes and even if an object is deleted.

• Lifecycle Rules: Versioning can be integrated with lifecycle rules, allowing you to automate the transition of object versions between different storage tiers.

• Supports MFA: Versioning supports multi-factor authentication, adding an extra layer of security to protect your data.

S3 Lifecycle Management

• Automates moving objects between different storage tiers.

• Can be used in conjunction with versioning.

• Can be applied to current versions and previous versions.

Auto Scaling

Dynamic Scaling Policies

• When a CloudWatch Alarm is triggered (ex: CPU > 70%), then add 2 units • When CloudWatch alarm is triggered (ex: CPU < 30%), then remove 1

• Anticipate a scaling based on known usage patterns • Ex: increase the min capacity to 10 at 5pm on Fridays

What is ECS?

• ECS - Elastic Container Service • Launch Docker containers on AWS You must provision & maintain the infrastructure (the EC2 instances) • AWS takes care of starting/Stopping containers • You can integrate Application Load Balancer

What is Fargate?

• Launch Docker containers on AWS • You do not provision & maintain the infrastructure (no EC2 instances) • Serverless offering • AWS just runs containers for you based on the CPU/RAM you need

ECS Task Definitions

1. Task Definitions are metadata in JSON format to tell ECS how to Run a Docker Container. It Contains Crucial Information like: • Image Name • Port Binding for Container and Host • Memory and CPU Required • Environment Variables • Networking Information • IAM Role • Logging Configurations (ex: CloudWatch) • Internet Gateway

ECS IAM Roles Deep Dive

1. Allow Each Task to Have a Specific Role

2. Use Different Roles for the Different ECS Services you Run

3. Task Role is Defined in the Task Definition

1. ECS Services Help Define How Many Tasks Should Run and How They should be Run.

2. They Ensure that the Number of Tasks Desired is Running Across our Fleet of EC2 Instance.

3. They can be Linked to ELB / NLB / ALB if Needed

4. You Can Run Task Without ECS Services!

AWS Lamda

Limitations:

1. Functions will timeout after 15 minutes.

2. The amount of RAM available ranges from 128MB to 3008MB with a 64MB increment between each option.

3. The Lambda code should not exceed 250mb in size, and the zipped version should be no larger than 50mb

4. There is a limit of 1,000 requests that can run concurrently, any request above this limit will be throttled and will need to wait for other functions to finish running.

Elastic Beanstalk

• Deploy and Scale: Deploys and scales your web applications, including the web application server platform.

• Programming Languages: Java, PHP, Python, Ruby, Go, Docker, .NET, Node.js.

• Application Servers: Apache http Server, Tomcat, Passenger, Puma, Nginx, and IIS.

• Provision AWS Resources: Provisions the AWS resources for you, e.g. EC2, RDS, S3, Elastic Load Balancers, Auto Scaling Groups, etc.

• Systems Administration: OS and application server updates. Monitoring, metrics, and health checks are all included.

• Administrative Control: Can fully manage the EC2 instances for you or you can take full administrative control.

RDS

RDS Automated Backup

• Point-In-Time Recovery: Recover your database to any point in time within a "retention period" of 1-35 days.

• Full Daily Backup: RDS takes a full daily backup, or snapshot, and also stores transaction logs throughout the day.

• The Recovery Process: When you perform a recovery, AWS will first choose the most recent daily backup. AWS then applies transaction logs relevant to that day, up to the recovery point.

RDS Snapshots:

• Snapshots are not automated: DB Snapshots are performed manually, meaning they are initiated by the user.

• No Retention Period: Manual snapshots are not deleted, even if the original RDS instance, along with any automated backups, is deleted.

• Backup to a Known State: You have the ability to back up your DB instance to a known state as frequently as desired. This allows you to restore to a specific state at any given time.

Migration of Database from EC2 to RDS Database:

# ec2db is the current db 
# rdsdb is the RDS db which is created when RDS is configured.
# -p = password
# -P = port
mysqldump -u root -p ec2db > ec2db.sql
mysql -h <replace-rds-end-point-here> -P 3306 -u rdsuser -p rdsdb < ec2db.sql
mysql -h <replace-rds-end-point-here> -P 3306 -u rdsuser -p

# Commands to check the db if migrated properly 
USE rdsdb
SELECT * FROM table1;

1. Sign-up and sign-in options for your apps.

2. Access for guest users.

3. Acts as an identity broker between you, eliminating the need for writing custom code.

4. Synchronizes user data across multiple devices.

5. Integration with social media authentication and web ID providers.

SQl vs NoSQL

Amazon Aurora

• 5x Performance: Amazon Aurora offers up to 5 times better performance compared to MySQL and 3 times better performance compared to PostgreSQL databases.

• Lower Price Point: Despite the improved performance, Aurora is available at a much lower price point, making it a cost-effective choice for applications requiring high performance.

• Similar Performance and Availability: While delivering enhanced performance, Aurora maintains similar levels of performance and availability as traditional relational databases, ensuring reliability and uptime for your applications.

Amazon DynamoDB

1. NoSQL Database: DynamoDB supports both document and key-value data models, allowing you to store and retrieve data in a flexible manner.

2. Fully Managed: DynamoDB is a fully managed database service, meaning AWS handles administrative tasks such as hardware provisioning, setup, configuration, and maintenance, allowing you to focus on developing your applications.

3. Scalability: DynamoDB scales seamlessly to handle any amount of traffic and data, automatically adjusting its capacity to meet your application's needs. It can handle millions of requests per second and trillions of rows, making it suitable for applications with high traffic and demanding workloads.

4. Low Latency: With its optimized architecture, DynamoDB delivers consistent, single-digit millisecond latency, enabling fast read and write operations. This makes it well-suited for real-time applications and use cases that require rapid data access.

5. Versatility: DynamoDB is widely applicable and can be used for a variety of applications such as mobile, web, gaming, ad-tech, IoT, and more. Its flexible data model and reliable performance make it a suitable choice for diverse use cases.

Route53

1. Domain registration

2. DNS routing

3. Health checking.

• Public hosted zones, which hold records specifying how to route internet-based traffic.

• Private hosted zones, which hold records specifying how to route traffic within a VPC.