#!/bin/bash

SOURCE_DIR="/var/www/html"
DEST_DIR="/home/user/backups"
ARCHIVE_NAME="backup_$(date +%Y%m%d_%H%M%S).tar.gz"

echo "Arch is begin: $SOURCE_DIR"

mkdir -p "$DEST_DIR"

tar -czf "$DEST_DIR/$ARCHIVE_NAME" "$SOURCE_DIR"

if [ $? -eq 0 ]; then
    echo "Arch Done!: $DEST_DIR/$ARCHIVE_NAME"
else
    echo "ALARMA!!!"
fi

# find "$DEST_DIR" -name "backup_*.tar.gz" -type f -mtime +7 -delete
# echo "Old is DELETED!"

В планировщик на каждые 12 часов

0 */12 * * * /home/backup.sh > /dev/null 2>&1