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VCUBE APP — 3-TIER DEPLOYMENT (WEB SERVER + APP SERVER + MYSQL DB SERVER) IN UBUNTU

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OVERVIEW

+--------------------+         +--------------------+         +--------------------+
|    Web Server      |  --->   |    App Server      |  --->   |    DB Server       |
|  (Flask Frontend)  |         | (Flask + SQLAlchemy|         |    (MySQL DB)      |
|  Port: 5000        |         |  + JWT Auth)       |         |  Port: 3306        |
+--------------------+         +--------------------+         +--------------------+

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STEP 1: DATABASE SERVER SETUP

1. Install MySQL

sudo apt update
sudo apt install mysql-server -y
sudo systemctl enable mysql
sudo systemctl start mysql

2. Secure MySQL

sudo mysql_secure_installation

VALIDATE PASSWORD COMPONENT can be used to test passwords and improve security. It checks the strength of password and allows the users to set only those passwords which are secure enough. Would you like to setup VALIDATE PASSWORD component?

Press y|Y for Yes, any other key for No: n

Remove anonymous users? (Press y|Y for Yes, any other key for No) : y

Disallow root login remotely? (Press y|Y for Yes, any other key for No) : y

Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y

Reload privilege tables now? (Press y|Y for Yes, any other key for No) : y

If it doesn’t ask for a root password — that’s fine (Ubuntu uses auth_socket authentication).

3. Log into MySQL as root

sudo mysql

4. Create application database and user

Inside MySQL shell:

CREATE DATABASE appdb;
CREATE USER 'appuser'@'%' IDENTIFIED WITH mysql_native_password BY 'app123';
GRANT ALL PRIVILEGES ON appdb.* TO 'appuser'@'%';
FLUSH PRIVILEGES;
EXIT;

5. Enable remote connections

sudo vim /etc/mysql/mysql.conf.d/mysqld.cnf

Find this line:

bind-address = 127.0.0.1

Change it to:

bind-address = 0.0.0.0

Then restart MySQL:

sudo systemctl restart mysql

6. Verify user and plugin

sudo mysql

SELECT user, host, plugin FROM mysql.user;

You should see:

| appuser | % | mysql_native_password |

That means Flask’s mysqlclient driver can connect successfully.

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STEP 2: APP SERVER SETUP (Flask Backend)

1. Install Python and build dependencies

sudo apt update
sudo apt install python3-full python3-pip pkg-config python3-dev default-libmysqlclient-dev build-essential -y

2. Clone repository and move to app_server folder

git clone https://github.com/kushall1845/Vcube_App.git
cd Vcube_App/app_server

3. Create and activate virtual environment

python3 -m venv venv
source venv/bin/activate

4. Install dependencies including mysqlclient

pip install -r requirements.txt
pip install mysqlclient

To verify installation:

pip show mysqlclient

5. Set environment variables

export DATABASE_URL="mysql://appuser:app123@<DB_SERVER_PRIVATE_IP>/appdb"
export SECRET_KEY="supersecretkey"
export APP_HOST="0.0.0.0"
export APP_PORT=5001

(Replace <DB_SERVER_PRIVATE_IP> with your MySQL instance’s private IP)

6. Initialize database tables

python3

from app import app, db
with app.app_context():
    db.create_all()

double click on enter after pasting

To exit

exit()

If no error, tables are created in appdb.

You can verify on DB server:

sudo mysql

USE appdb;

SHOW TABLES;

Should show:

| user |

7. Run app in background (APP SERVER)

nohup python3 app.py > app_server.log 2>&1 &

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STEP 3: WEB SERVER SETUP (Frontend)

1. Install Python

sudo apt update
sudo apt install python3-full python3-pip -y

2. Clone repository and move to web_server folder

git clone https://github.com/kushall1845/Vcube_App.git
cd Vcube_App/web_server

3. Create and activate virtual environment

python3 -m venv venv
source venv/bin/activate

4. Install dependencies

pip install -r requirements.txt

5. Set environment variables

export APP_INTERNAL="http://<APP_SERVER_PRIVATE_IP>:5001"
export WEB_HOST="0.0.0.0"
export WEB_PORT=5000

(Replace <APP_SERVER_PRIVATE_IP> with your Backend instance’s private IP)

6. Allow port and run frontend in background

nohup python3 app.py > web_server.log 2>&1 &

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STEP 4: ACCESS THE APPLICATION

Open your browser and visit:

http://<PUBLIC_IP_OF_WEB_SERVER>:5000

The Web Server proxies API requests to:

http://<APP_SERVER_PRIVATE_IP>:5001

which connects to:

<DB_SERVER_PRIVATE_IP>:3306

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STEP 5: VERIFY CONNECTIVITY

From App Server → DB Server

mysql -h <DB_SERVER_PRIVATE_IP> -u appuser -p

From Web Server → App Server

curl http://<APP_SERVER_PRIVATE_IP>:5001/api/health

Expected:

{"status": "ok"}

From Browser → Web Server

http://<PUBLIC_IP_WEB_SERVER>:5000

You should see the VCube App interface.

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RESULT SCREENSHOT

TO VIEW DATABASE

NOTE

Make sure the following ports are accessible in your AWS Security Groups or Firewall settings:

Port 5000 → Web Server (Frontend)

Port 5001 → App Server (Flask Backend)

Port 3306 → DB Server (MySQL)

Port 22 → SSH (for remote access to all servers)

These ports must be open for communication between respective servers.

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SUMMARY OF IP FLOW

Component	Example Private/Public IP	Port	Description
Web Server	<public_ip_web>	5000	User interface (frontend)
App Server	<private_ip_app>	5001	Flask API + JWT + Logic
DB Server	<private_ip_db>	3306	MySQL database

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