AWS Well Architected Solutions on Twitch.TV/AWS - Reliability Pillar

rel1.md

REL 1: How are you managing AWS service limits for your accounts?

AWS Service Limits

Active monitoring and managing limits

AWS Service Limits API

AWS Trusted Advisor Adds Service Limit Dashboard and CloudWatch Metrics

Create AWS CloudWatch Alarm on the Number of Running EC2 Instances

AWS Config Rules – Dynamic Compliance Checking for Cloud Resources

Using the AWS Config Service to Detect Unexpected Resource Usage

Implemented automated monitoring and management of limits

AWS Limit Monitor

$ aws support describe-trusted-advisor-check-result
--check-id eW7HH0l7J9
--query 'result.sort_by(flaggedResources[?status!="ok"],&metadata[2])[].metadata'
--output table
--region us-east-1

Aware of fixed service limits

Ensure there is a sufficient gap between the current service limit and the max usage to accommodate for fail over

• How much redundancy should you provision? (domino effect vs. waste)

Flux: A New Approach to System Intuition

"In this situation we don’t have enough extra capacity running hot to instantly fail over, so scaling up takes some time."

Service limits are managed across all relevant accounts andr egions

Remember that service limits are usually per-region

Partner Tools

Clean Cloud(https://imgur.com/gallery/vAMGxZJ)

rel2.md

REL 2 How do you plan your network topology on AWS?

Connectivity back to data center is not needed

Consider startup vs. enterprise / new vs migration

Highly available connectivity between AWS and on-premises environment is implemented

AWS Direct Connect

Amazon VPC - VPN Connections

AWS Marketplace - OpenVPN

Multiple Data Center HA Network Connectivity

Multiple Region Multi-VPC Connectivity

Highly available network connectivity for the users of the workload is implemented

Amazon Route53

• Routing Policies
• Health Checks
• ALIAS Records

Amazon CloudFront

• Cache Expiration
• Lambda@Edge
• Serving Secure Content
• [Serving Compressed Files][https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/ServingCompressedFiles.html]

Elastic Load Balancing

• Application Load Balancer
• Network Load Balancer
• Classic Load Balancer

Using static IP addresses for Application Load Balancers

AWS Marketplace - F5 Networks

AWS Marketplace - KEMP Technologies

Using non-overlapping private IP address ranges in multiple VPCs

https://en.wikipedia.org/wiki/Private_network

10.0.0.0 – 10.255.255.255 172.16.0.0 – 172.31.255.255 192.168.0.0 – 192.168.255.255

IP subnet allocation accounts for expansion and availability

• Auto Scaling
• Load Balancer

rel3.md

How does your system adapt to changes in demand?

Workload scales automatically

• "Global"
• "Serverless"
• "AutoScaling"
• "Provisioned"

Workload is load tested

JMeter

Gatling

Locust

Vegeta

BeesWithMachineguns

ServerlessArtillery

Grinder

vpc.yaml

AWSTemplateFormatVersion: '2010-09-09'
Parameters:
  CidrBlock:
    Type: String
    Default: 192.168.0.0/16
    Description: CIDR block for environment
  SubnetPubACidr:
    Type: String
    Default: 192.168.1.0/24
    Description: CIDR block for environment
  SubnetPubBCidr:
    Type: String
    Default: 192.168.3.0/24
    Description: CIDR block for environment
  SubnetPvtACidr:
    Type: String
    Default: 192.168.2.0/24
    Description: CIDR block for environment
  SubnetPvtBCidr:
    Type: String
    Default: 192.168.4.0/24
    Description: CIDR block for environment            
Resources:
  EnvironmentVPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: !Ref CidrBlock
      EnableDnsSupport: 'false'
      EnableDnsHostnames: 'false'
      InstanceTenancy: default
  SubnetPubA:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref EnvironmentVPC
      CidrBlock: !Ref SubnetPubACidr
      MapPublicIpOnLaunch: true
      AvailabilityZone: !Select 
        - 0
        - Fn::GetAZs: !Ref 'AWS::Region'
  SubnetPubB:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref EnvironmentVPC
      CidrBlock: !Ref SubnetPubBCidr
      MapPublicIpOnLaunch: true
      AvailabilityZone: !Select 
        - 1
        - Fn::GetAZs: !Ref 'AWS::Region'
  SubnetPvtA:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref EnvironmentVPC
      CidrBlock: !Ref SubnetPvtACidr
      MapPublicIpOnLaunch: false
      AvailabilityZone: !Select 
        - 0
        - Fn::GetAZs: !Ref 'AWS::Region'
  SubnetPvtB:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref EnvironmentVPC
      CidrBlock: !Ref SubnetPvtBCidr
      MapPublicIpOnLaunch: false
      AvailabilityZone: !Select 
        - 1
        - Fn::GetAZs: !Ref 'AWS::Region'
  GatewayToInternet:
    Type: AWS::EC2::InternetGateway
  InternetGatewayAttachment:
    Type: AWS::EC2::VPCGatewayAttachment
    Properties:
      VpcId: !Ref EnvironmentVPC
      InternetGatewayId: !Ref GatewayToInternet
  PubRouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId: !Ref EnvironmentVPC
  PvtRouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId: !Ref EnvironmentVPC
  PubToInternet:
    Type: AWS::EC2::Route
    DependsOn: GatewayToInternet
    Properties:
      RouteTableId: !Ref PubRouteTable
      DestinationCidrBlock: 0.0.0.0/0
      GatewayId: !Ref GatewayToInternet
  PubARouteTableAssociaton:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref SubnetPubA
      RouteTableId: !Ref PubRouteTable
  PubBRouteTableAssociaton:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref SubnetPubB
      RouteTableId: !Ref PubRouteTable
  PvtARouteTableAssociaton:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref SubnetPvtA
      RouteTableId: !Ref PvtRouteTable
  PvtBRouteTableAssociaton:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref SubnetPvtB
      RouteTableId: !Ref PvtRouteTable                  
  NatGateway:
    Type: AWS::EC2::NatGateway
    Properties:
      AllocationId:
        Fn::GetAtt:
        - EIP
        - AllocationId
      SubnetId:
        Ref: SubnetPubA
  EIP:
    Type: AWS::EC2::EIP
    Properties:
      Domain: vpc
  NatRoute:
    Type: AWS::EC2::Route
    Properties:
      RouteTableId:
        Ref: PvtRouteTable
      DestinationCidrBlock: 0.0.0.0/0
      NatGatewayId:
        Ref: NatGateway