Sample bash script for AWS to take backups of your MySQL DB

aws_backup.sh

#!/bin/bash

# Sample backup file

# aws cli needs to be installed first and configured
# https://sst.dev/chapters/create-an-iam-user.html 
# above link will help you to create an IAM user and configure aws cli

# This script only works on the same machine where the MySQL server is running,
# If you want to use this script on a different machine, you need to also add the hostname and port to the mysqldump command
# e.g mysqldump -h hostname -P port -u $DB_USER -p$DB_PASS $db_name | gzip > $backup_file
# because at default it assumes that the MySQL server is running on the same machine

# MySQL credentials
DB_USER="your_db_user"
DB_PASS="your_db_password"
DB_NAME_1="DB_NAME_1"
DB_NAME_2="DB_NAME_2"
DB_NAME_3="DB_NAME_3"

# Backup directory
BACKUP_DIR="/storage/backup"

# AWS S3 details
S3_BUCKET="your_aws_s3_bucket_name"
S3_PREFIX="mysql_backups"  # Optional: S3 prefix for organizing backups

# Create backup directory if it doesn't exist
mkdir -p $BACKUP_DIR

# Generate timestamp
TIMESTAMP=$(date +"%Y%m%d_%H%M%S")

# Function to backup a database and upload to S3
backup_and_upload() {
    local db_name=$1
    local backup_file="$BACKUP_DIR/${db_name}_${TIMESTAMP}.sql.gz"
    
    echo "Backing up $db_name..."
    mysqldump -u $DB_USER -p$DB_PASS $db_name | gzip > $backup_file
    
    echo "Uploading $db_name backup to S3..."
    aws s3 cp $backup_file s3://${S3_BUCKET}/${S3_PREFIX}/${db_name}_${TIMESTAMP}.sql.gz
    
    if [ $? -eq 0 ]; then
        echo "Successfully backed up and uploaded $db_name"
    else
        echo "Error backing up or uploading $db_name"
    fi
}

# Backup and upload each database
backup_and_upload $DB_NAME_1
backup_and_upload $DB_NAME_2
backup_and_upload $DB_NAME_3

# Delete local backups older than 7 days
echo "Cleaning up local backups older than 7 days..."
find $BACKUP_DIR -name "*.sql.gz" -type f -mtime +7 -delete

# Delete S3 objects older than 7 days
echo "Cleaning up S3 backups older than 7 days..."
aws s3 ls s3://${S3_BUCKET}/${S3_PREFIX}/ | while read -r line;
do
    createDate=`echo $line|awk {'print $1" "$2'}`
    createDate=`date -d"$createDate" +%s`
    olderThan=`date -d"-7 days" +%s`
    if [[ $createDate -lt $olderThan ]]
    then
        fileName=`echo $line|awk {'print $4'}`
        if [[ $fileName != "" ]]
        then
            aws s3 rm s3://${S3_BUCKET}/${S3_PREFIX}/$fileName
            echo "Deleted old S3 backup: $fileName"
        fi
    fi
done

echo "Backup process completed"