🚀 Automating MySQL Backups with Bash Script & Cron

Databases are the heart of most applications—and losing them can be a nightmare. Manual backups work for quick fixes, but in production environments, automated MySQL backups are essential.

In this guide, we’ll build a simple Bash script to back up MySQL databases, compress them, keep them for a fixed number of days, and schedule it with cron.

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🔑 Why Automate Backups?

• ✅ Ensures you always have a recent copy of your data
• ✅ Reduces risk of human error
• ✅ Saves time compared to manual exports
• ✅ Easy to restore when disaster strikes

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🛠 Prerequisites

• A Linux server with MySQL/MariaDB installed
• A user with access to all databases you want to back up
• Basic knowledge of shell commands

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1) Login as Root

sudo -i

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2) Create a Backup Folder & Script File

mkdir -p /home/backup
touch /home/backup/backup-mysql.sh
nano /home/backup/backup-mysql.sh

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3) Add the Backup Script

Paste this inside the file:

#!/bin/bash
#----------------------------------------
# MySQL Backup Script
#----------------------------------------

# 🔧 Configuration
HOST='mysql-localhost'      # MySQL server host
USER='mysql-username'       # Username
PASSWORD='mysql-password'   # Password
DAYS_TO_KEEP=5              # Delete backups older than X days
GZIP=1                      # 1 = gzip compression, 0 = plain .sql
BACKUP_PATH='/home/backup/mysql'   # Location to store backups
TIMESTAMP=$(date +"%d_%m_%Y_%H_%M_%S")   # Date-time for unique file names

#----------------------------------------

# 📂 Create backup folder if not exists
if [ ! -d "$BACKUP_PATH" ]; then
  mkdir -p "$BACKUP_PATH"
fi

# 📋 Get database list
databases=$(mysql -h "$HOST" -u "$USER" -p"$PASSWORD" -e "SHOW DATABASES;" | tr -d "|" | grep -v Database)

# 🔄 Loop through databases
for db in $databases; do
  # Skip system databases
  if [ "$db" = 'information_schema' ] || [ "$db" = 'performance_schema' ] || [ "$db" = 'mysql' ] || [ "$db" = 'sys' ]; then
    echo "Skipping database: $db"
    continue
  fi

  # Backup (with or without compression)
  if [ "$GZIP" -eq 0 ]; then
    echo "Backing up database: $db (no compression)"
    mysqldump -h "$HOST" -u "$USER" -p"$PASSWORD" --databases "$db" --single-transaction --quick > "$BACKUP_PATH/${db}-${TIMESTAMP}.sql"
  else
    echo "Backing up database: $db (with compression)"
    mysqldump -h "$HOST" -u "$USER" -p"$PASSWORD" --databases "$db" --single-transaction --quick | gzip -c > "$BACKUP_PATH/${db}-${TIMESTAMP}.gz"
  fi
done

# 🧹 Delete old backups
if [ "$DAYS_TO_KEEP" -gt 0 ]; then
  echo "Deleting backups older than $DAYS_TO_KEEP days"
  find "$BACKUP_PATH"/* -mtime +"$DAYS_TO_KEEP" -exec rm {} \;
fi

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4) Make the Script Executable

chmod +x /home/backup/backup-mysql.sh

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5) Test the Script

Run it manually:

/home/backup/backup-mysql.sh

Backups will be stored inside:

/home/backup/mysql/

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6) Automate with Cron

Open crontab:

crontab -e

Add this line to run the backup daily at 11:30 PM:

30 23 * * * /home/backup/backup-mysql.sh >/dev/null 2>&1

Restart cron service:

sudo systemctl restart cron

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🧠 How It Works (Script Breakdown)

• Configuration variables → Define MySQL credentials, backup path, retention days.
• Timestamp → Ensures unique filenames (dbname-24_08_2025_23_30_00.sql.gz).
• Database filtering → Skips system databases (information_schema, etc.).
• mysqldump with --single-transaction → Ensures consistent snapshot for InnoDB without locking tables.
• gzip compression → Saves space.
• Retention policy (find -mtime) → Deletes backups older than 5 days.

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✅ Conclusion

With just a few lines of Bash and a cron job, you’ve automated MySQL backups.

• Backups run every day at 11:30 PM
• Old backups older than 5 days are automatically removed
• The script is simple to extend for remote storage, logging, or notifications

Automating backups is a small investment that can save you hours—or even your entire project—in case of data loss.