Backup with Rotation Script

Overview

A robust backup script with automatic rotation to manage disk space. Supports multiple retention policies: daily, weekly, and monthly backups.

The Script

#!/bin/bash
# Backup with Rotation
# Usage: ./backup-rotate.sh <source> <backup_dir>

set -euo pipefail

# Configuration
KEEP_DAILY=7
KEEP_WEEKLY=4
KEEP_MONTHLY=6

# Timestamp formats
DATE_DAILY=$(date +%Y-%m-%d)
DATE_WEEKLY=$(date +%Y-W%V)
DATE_MONTHLY=$(date +%Y-%m)
TIMESTAMP=$(date +%Y-%m-%d_%H%M%S)

SOURCE="$1"
BACKUP_DIR="$2"

# Create backup directories
DAILY_DIR="$BACKUP_DIR/daily"
WEEKLY_DIR="$BACKUP_DIR/weekly"
MONTHLY_DIR="$BACKUP_DIR/monthly"

mkdir -p "$DAILY_DIR" "$WEEKLY_DIR" "$MONTHLY_DIR"

# Get source name for backup filename
SOURCE_NAME=$(basename "$SOURCE")

echo "Starting backup of $SOURCE"

# Create daily backup
DAILY_BACKUP="$DAILY_DIR/\${SOURCE_NAME}_\${TIMESTAMP}.tar.gz"

tar -czf "$DAILY_BACKUP" -C "$(dirname "$SOURCE")" "$(basename "$SOURCE")"

BACKUP_SIZE=$(du -h "$DAILY_BACKUP" | cut -f1)
echo "Daily backup created: $BACKUP_SIZE"

# Rotation - remove old backups
find "$DAILY_DIR" -name "\${SOURCE_NAME}_*" -mtime +$KEEP_DAILY -delete 2>/dev/null || true
find "$WEEKLY_DIR" -name "\${SOURCE_NAME}_*" -mtime +$((KEEP_WEEKLY * 7)) -delete 2>/dev/null || true
find "$MONTHLY_DIR" -name "\${SOURCE_NAME}_*" -mtime +$((KEEP_MONTHLY * 30)) -delete 2>/dev/null || true

echo "Backup complete!"

Usage

# Basic backup
./backup-rotate.sh /var/www /backups/www

# Compressed backup with custom retention
./backup-rotate.sh -c -d 14 -w 8 ~/documents /backups/docs

# With exclude file
./backup-rotate.sh -e exclude.txt /home /backups/home

Cron Setup

# Daily backup at 2 AM
0 2 * * * /usr/local/bin/backup-rotate.sh -c /var/www /backups/www >> /var/log/backup.log 2>&1