Setting Up Offsite Backups to S3-Compatible Storage

Why Offsite?

Local backups protect against accidental deletion but not against hardware failure, datacenter incidents, or ransomware. Offsite backups to S3-compatible storage provide geographic redundancy.

Install AWS CLI

sudo apt install -y awscli

Configure Credentials

aws configure
# Enter your Access Key ID, Secret Key, Region, and output format
# For non-AWS S3 providers, configure the endpoint separately

Basic Backup Script

#!/bin/bash
DATE=$(date +%Y%m%d)
BUCKET="s3://my-backups/$(hostname)"

# Database backup
mysqldump -u root --all-databases --single-transaction | gzip > /tmp/db_${DATE}.sql.gz

# Upload to S3
aws s3 cp /tmp/db_${DATE}.sql.gz ${BUCKET}/databases/

# Upload web files
tar -czf /tmp/www_${DATE}.tar.gz /var/www
aws s3 cp /tmp/www_${DATE}.tar.gz ${BUCKET}/files/

# Upload configs
tar -czf /tmp/etc_${DATE}.tar.gz /etc
aws s3 cp /tmp/etc_${DATE}.tar.gz ${BUCKET}/configs/

# Clean up local temp files
rm /tmp/db_${DATE}.sql.gz /tmp/www_${DATE}.tar.gz /tmp/etc_${DATE}.tar.gz

# Remove S3 backups older than 30 days
aws s3 ls ${BUCKET}/databases/ | awk '{print $4}' | while read file; do
    file_date=$(echo "$file" | grep -oP '\d{8}')
    if [ "$(date -d "$file_date" +%s)" -lt "$(date -d "30 days ago" +%s)" ]; then
        aws s3 rm "${BUCKET}/databases/${file}"
    fi
done

echo "Backup completed: $(date)"

Schedule with Cron

0 2 * * * /root/scripts/s3-backup.sh >> /var/log/s3-backup.log 2>&1