readme.md

Deploy 2 VMs in Different Subnets, Configure MariaDB and Apache

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Objective

1. Create two VMs:

   • VM-1: Install MariaDB in subnet 192.* (e.g., 192.168.1.0/24).
   • VM-2: Install Apache in subnet 10.* (e.g., 10.0.1.0/24).

2. Configure firewalls and routes to allow connectivity between the VMs.

3. Allow VM-2 to connect to MariaDB running on VM-1.

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Prerequisites

1. Google Cloud Platform Setup:

   • GCP project with billing enabled.
   • Install and configure gcloud CLI:

     gcloud init

2. Enable Required APIs:

   gcloud services enable compute.googleapis.com

3. IAM Permissions: Ensure permissions to create VMs, VPC networks, subnets, and firewall rules.

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Step 1: Create a VPC Network and Subnets

1. Create a VPC Network:

   gcloud compute networks create custom-vpc --subnet-mode=custom

2. Create Subnet-1 (192.*):

   gcloud compute networks subnets create subnet-192 \
       --network=custom-vpc \
       --range=192.168.1.0/24 \
       --region=us-central1

3. Create Subnet-2 (10.*):

   gcloud compute networks subnets create subnet-10 \
       --network=custom-vpc \
       --range=10.0.1.0/24 \
       --region=us-central1

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Step 2: Create Two VM Instances

Create VM-1 (MariaDB Server in Subnet-192)

gcloud compute instances create mariadb-vm \
    --zone=us-central1-a \
    --machine-type=e2-micro \
    --subnet=subnet-192 \
    --metadata=startup-script='#! /bin/bash
        apt-get update
        apt-get install -y mariadb-server
        systemctl start mariadb
        systemctl enable mariadb
        mysql -e "CREATE DATABASE demo_db;"
        mysql -e "CREATE USER '\''apacheuser'\''@'\''10.0.1.%'\'' IDENTIFIED BY '\''password123'\'';"
        mysql -e "GRANT ALL PRIVILEGES ON demo_db.* TO '\''apacheuser'\''@'\''10.0.1.%'\'';"
        mysql -e "FLUSH PRIVILEGES;"
        echo "MariaDB setup complete."
    ' \
    --tags=mariadb-server \
    --boot-disk-size=10GB

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Create VM-2 (Apache Server in Subnet-10)

gcloud compute instances create apache-vm \
    --zone=us-central1-a \
    --machine-type=e2-micro \
    --subnet=subnet-10 \
    --metadata=startup-script='#! /bin/bash
        apt-get update
        apt-get install -y apache2 php php-mysql
        systemctl start apache2
        systemctl enable apache2
        echo "<?php
        \$conn = new mysqli(\"192.168.1.2\", \"apacheuser\", \"password123\", \"demo_db\");
        if (\$conn->connect_error) { die(\"Connection failed: \" . \$conn->connect_error); }
        echo \"<h1>Data from MariaDB</h1>\";
        \$result = \$conn->query(\"SHOW DATABASES\");
        while (\$row = \$result->fetch_assoc()) {
            echo \"Database: \" . \$row[\"Database\"] . \"<br>\";
        }
        ?>" > /var/www/html/index.php
    ' \
    --tags=apache-server \
    --boot-disk-size=10GB

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Step 3: Configure Firewall Rules

1. Allow MariaDB Traffic (Port 3306) to Subnet-10:

   gcloud compute firewall-rules create allow-mariadb \
       --network=custom-vpc \
       --allow=tcp:3306 \
       --source-ranges=10.0.1.0/24 \
       --target-tags=mariadb-server

2. Allow HTTP Traffic to Apache Server:

   gcloud compute firewall-rules create allow-http \
       --network=custom-vpc \
       --allow=tcp:80 \
       --source-ranges=0.0.0.0/0 \
       --target-tags=apache-server

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Step 4: Verify Connectivity

1. Find Internal IPs:

   • List the instances:

     gcloud compute instances list

   • Note the internal IP of mariadb-vm (e.g., 192.168.1.2).

2. Test Apache Server:

   • Open the external IP of apache-vm in a browser:

     http://<APACHE-VM-EXTERNAL-IP>
     

   • You should see the output confirming the connection to MariaDB and listing the databases:

     Data from MariaDB
     Database: demo_db
     

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Step 5: Cleanup (Optional)

1. Delete VMs:

   gcloud compute instances delete mariadb-vm apache-vm --zone=us-central1-a

2. Delete Firewall Rules:

   gcloud compute firewall-rules delete allow-mariadb allow-http

3. Delete VPC Network:

   gcloud compute networks delete custom-vpc

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Summary

1. Two VMs were created in different subnets:

   • mariadb-vm (Subnet: 192.168.1.0/24) hosting MariaDB.
   • apache-vm (Subnet: 10.0.1.0/24) hosting Apache with PHP.

2. Firewall Rules were configured to allow:

   • Port 3306 for MariaDB from 10.* subnet.
   • Port 80 for HTTP access to Apache.

3. The PHP script on the Apache server successfully connected to the MariaDB server and displayed demo data.

Your setup is now complete! 🎉