Centralized Backup Server with rsync and cron on Red Hat Linux

Today’s project is both practical and RHCSA-aligned: setting up a secure, automated backup server using rsync over SSH and scheduled jobs with cron.

This is a real-world admin task and also mirrors RHCSA exam scenarios where backup automation and file transfer are common.

🔧 Objective

• Use rsync to transfer files securely over SSH
• Automate regular backups with cron
• Secure access using SSH keys
• Harden access with firewall and permissions

📚 RHCSA Skills Covered

✔ User and permission management

✔ SSH key authentication

✔ Automating jobs with cron

✔ File transfer with rsync

✔ Firewall configuration

1️⃣ Install rsync

sudo dnf install -y rsync

Check version:
rsync --version

2️⃣ Set Up SSH Key Authentication

On client machine (sending data):

ssh-keygen -t rsa

ssh-copy-id backupuser@backupserver

Now the client can connect without a password:

ssh backupuser@backupserver

3️⃣ Create a Backup Directory on the Server

sudo mkdir -p /backups/home
sudo chown backupuser:backupuser /backups/home

4️⃣ Test rsync Manually

From client to server:
rsync -avh /home/backupuser/Documents/
backupuser@backupserver:/backups/home/

Flags:

-a: archive mode (preserves permissions)
-v: verbose
-h: human-readable output

5️⃣ Automate Backups with cron

On the client:
crontab -e

Add this line to run backup every day at 2 AM:

0 2 * * * rsync -az /home/backupuser/Documents/ backupuser@backupserver:/backups/home/

Check your cron jobs:
crontab -l

6️⃣ Secure the Backup Server

Allow SSH and rsync port (default is SSH):
sudo firewall-cmd --add-service=ssh --permanent
sudo firewall-cmd --reload

🧪 Try It Yourself

• Schedule hourly or weekly backups
• Add logging with rsync -avh --log-file=/var/log/backup.log
• Create a backup rotation script (daily, weekly folders)
• Test by restoring files from the server

✅ Recap

Task	Tool/Command
Generate SSH keys	ssh-keygen, ssh-copy-id
Create backup folder	mkdir, chown
Transfer files securely	rsync -avh source destination
Schedule backups	crontab -e
Harden backup access	firewalld, SSH key-only login

🎯 Why This Matters (RHCSA)

Backups are critical for disaster recovery.

This project tested:

• SSH automation
• Cron scheduling
• Firewall management
• Basic scripting and file system management
• All of these are RHCSA core competencies.