🛡️ Linux Admin Project: Secure Bank Customer Portal with Automated Auditing

A Real-World Banking System Using useradd, chmod, ACLs, systemd, and More!

🚀 What if you could manage 10,000 bank customers using only Linux commands?
In this hands-on project, you’ll simulate a secure banking portal that handles users, enforces privacy, encrypts backups, and even triggers alerts on suspicious activity.

🏦 Scenario: You’re the Sysadmin for a Bank

Your Mission:

• Give employees admin access (but safely).
• Ensure customers can only access their data.
• Maintain daily encrypted transaction logs.
• Detect fraudulent logins in real time.

Let’s turn a regular Linux machine into a secure bank portal. 💻💸

## 📑 Table of Contents

• 🔧 Step 1: Create Users & Groups
• 💰 Step 2: Secure the Banking Directories
• 🔍 Step 3: Monitor Suspicious Activity
• ⏰ Step 4: Automate Encrypted Daily Backups
• 🏧 Step 5: Simulate a Customer Login
• 💻 Demo: Bank Customer Login Simulation

🔧 Step 1: Create Users & Groups

🛠 Tools: useradd, usermod, groups

# Employees and Customers

Similarly, Create Groups, Assign Users to groups

sudo groupadd employees
sudo groupadd customers

sudo usermod -aG employees manager teller
sudo usermod -aG customers john jane

✅ Why?

• Groups control permissions.
• Customers can’t peek into each other’s data.
• Employees can manage transactions but not compromise privacy.

💰 Step 2: Secure the Banking Directories

🛠 Tools: mkdir, chmod, chown, setfacl

# Create folders

# Permissions

# Let employees read but not write customer data

🔒 Why?

• chmod 700: Only the customer can access their folder.
• setfacl: Employees can view but not edit customer files.
• /bank/transactions: Editable only by employees.

🔍 Step 3: Monitor Suspicious Activity

🛠 Tools: grep, journalctl, find

# Failed logins (fraud detection)

sudo grep "Failed password" /var/log/auth.log

Similarly, You can Check Suspicious activity by these commands:

# Audit sudo usage

sudo journalctl -q | grep "sudo.*COMMAND"

# Detect changes in the last hour

sudo find /bank -type f -mmin -60 -ls

🚨 Why?

• Spot brute-force attacks and insider misuse.
• Know who’s using sudo, when, and for what.
• Track recent changes to sensitive files.

⏰ Step 4: Automate Encrypted Daily Backups

🛠 Tools: systemd, tar, gpg, cron

# 1. Backup script

# 2. Make executable

# 3. Systemd timer

# 4. Start the timer

🗝️ Why?

• Protects data even if the system is breached.
• Systemd ensures it runs reliably—even after reboot.

🏧 Step 5: Simulate a Customer Login

💻 Demo: Bank Customer Login Simulation

📘 Conclusion

With just a few Linux commands, you've built a:
✅ Secure multi-user bank portal
✅ Automated encrypted backups
✅ Real-time monitoring system

💡 Want to take it further? Add:

• Email alerts for suspicious logins
• Web frontend using Apache/Nginx
• PostgreSQL for storing balances

#30DaysLinuxChallenge #CloudWhisler
DevOps #Linux #RHCSA #Opensource #AWS #CloudComputing

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