Three Tier Web Application

In this AWS project, I configure and deploy phpMyadmin web application in a Three Tier architecture. The architecture of the project consists of the web tier (ALB), the application tier (php), and the database tier(MySQL RDS).

Network Architecture Consists of:

• A VPC.
• Two public subnets in two availability zones (Web Tier).
• Two private subnets in two availability zones (Application Tier).
• Two private subnets spread in two availability zones (Database Tier).
• Three route tables:
  1. public web route table that connects the public subnets to an internet gateway.
  2. private application route table that connect the Application Tier private subnets and a NAT gateway.
  3. private database route table that connect the Database Tier private subnets and a NAT gateway.
• An Internet Gateway connects an AWS VPC to the Internet.
• A NAT Gateway connects private subnets.

Network Project Steps:

1. Create a VPC
   • Go to AWS Concolse > VPC > Click Create VPC.
   • Give VPC a name and click Create VPC.
2. Create Subnets
   • Go to VPC > Subnets > Click Create Subnets.
   • For VPC ID, Select the VPC created early.
   • Create two public web subnets in two AZ.
   • Create two private application subnets in two AZ.
   • Create two private database subnets in two AZ.
3. Create Route tables
   • Go t0 VPC > Route tables > Click Create route table
   • For VPC ID, Select the VPC created early.
   • Create a public web, a private application and a private database route tables.
   • Map route table to subnets.
4. Create an Internet Gateway.
5. Create a NAT Gateway.
   • For Subnets choose web public subnets.
6. Add a route destination 0.0.0.0/0 in public web subnets and point to Internet Gateway.
7. Add a route destination 0.0.0.0/0 in private application subnets and point to NAT Gateway.
8. Add a route destination 0.0.0.0/0 in private database subnets and point to NAT Gateway.

Web and Application Tier Project Steps:

1. Create jump server EC2 instance
   • Go to EC2 > Instances > Click on Launch instances
   • Give instance a name for a jump server instance
   • Select Amazon Linux 2023 AMI and t2.micro free tier
   • Click Create new key pair and download to desktop/laptop
   • Select VPC created earlier and public web subnet
   • Enable public IP
   • Create new security group for jump server security group
   • Keep the rest as default
   • Click Launch instances
2. Create two private php server EC2 instances
   • Give instance a name for a private PHP server instance
   • Select Amazon Linux 2023 AMI and t2.micro free tier
   • Disable public IP
   • Create new php server security group
   • Click Launch instances
3. Create Application Load Balancing (ALB)
   • Create ALB Security Group.
   • Create Target Group.
   • Create Target Group Security Group.
4. Use SSH Client to connect to jump server
   • One login to jump server, Connect to private PHP sever.
   • Follow instruction to install Apache Sever and phpMyAdmin in both private PHP servers.
5. Go back to Load Balancing > Target Groups
   • Add the two private PHP servers to Target Groups.
   • Make sure the instances in healthy state

Database Tier Project Steps:

1. Create DB Subnet groups
   • Go to Amazon RDS > Subnet groups.
   • Give DB Subnet a name.
   • Choose two available zones.
   • Select the two subnet that we created for the database.
2. Create DB instance
   • Go to Database, click on Create database.
   • Give DB instance indentifier a name.
   • Inpute password and confirm.
   • Create new DB security group.
3. Allow PHP server to connect to DB instance
   • Add Custom TCP and port 3306 in DB security group for PHP sever security group.
4. Modify the config file in PHP server to point to DB end point
   • Use SSH client to login to PHP server.
   • Go to phpMyAdmin folder.
   • Edit the file config.inc.php.
   • Under Authentication section, change localhost to a DB end point.
5. Enable Stickiness session due to phpMyadmin is statefull apllication
   • Go EC2 > Target group select the target group
   • Select Attributes tab > Select Edit and enable Stickiness session