Creating an automated backup script for Koha, an open-source Integrated Library System (ILS), requires some careful consideration. Here's a basic example of a shell script that you can schedule to run regularly using cron on a Linux system. This script will backup your Koha database and files to a specified directory.

Firstly, ensure you have the necessary permissions to access the Koha database. You may need to adjust the username and password accordingly in the script.

```bash

#!/bin/bash

# Koha backup script

# Database credentials

DB_USER="your_database_username"

DB_PASSWORD="your_database_password"

DB_NAME="your_koha_database_name"

# Backup directory

BACKUP_DIR="/path/to/backup/directory"

# Date for backup file

DATE=$(date +"%Y-%m-%d")

# Dump Koha database

mysqldump -u $DB_USER -p$DB_PASSWORD $DB_NAME > $BACKUP_DIR/$DB_NAME-$DATE.sql

# Backup Koha files

tar czf $BACKUP_DIR/koha-files-$DATE.tar.gz /path/to/your/koha/installation

# Optional: Delete older backups to save space

#find $BACKUP_DIR -type f -name '*.tar.gz' -mtime +7 -exec rm {} \;

#find $BACKUP_DIR -type f -name '*.sql' -mtime +7 -exec rm {} \;

echo "Backup completed"

```

Replace `"your_database_username"`, `"your_database_password"`, `"your_koha_database_name"`, and `"/path/to/backup/directory"` with your actual database credentials and desired backup directory. 

Make sure to give execute permission to this script:

```bash

chmod +x koha_backup.sh

```

You can then schedule this script to run daily or weekly using cron:

```bash

crontab -e

```

Then add a line like this to schedule it to run every day at 2 AM:

```bash

0 2 * * * /path/to/koha_backup.sh

```

This script will dump your Koha database to a `.sql` file and compress your Koha files into a `.tar.gz` archive, appending the current date to the filenames. 

Adjust the backup frequency, retention policy, and any other parameters to fit your specific requirements. Additionally, make sure to test the script in a safe environment before deploying it to production.