El dia de hoy me pase la tarde intentando instalar Magento en mi Dreamhost, pero ni via web ni via ssh con el listado de comandos del wiki de magento he podido hasta, que buscando en foros me encontrado algunas pistas para la instalación via CLI (script), aquí les dejo como hacerlo automáticamente.

NOTA: con este script se hace muy bien desde cero, aunque toma su tiempo terminar la instalación ,asi que paciencia

#!/bin/bash

    dbhost="HOST DE LA DB";
    dbname="NOMBRE DE LA DB";
    dbuser="USUARIO DE LA DB";
    dbpass="PASSWORD";
    url="http://DOMINIO A SER INSTALADO";

    adminuser="USUARIO PARA ADMINISTRAR MAGENTO";
    adminpass="PASSWORD ADMINISTRATIVO";
    adminfname="NOMBRE DEL ADMIN";
    adminlname="APELLIDO DEL ADMIN";
    adminemail="ADMIN@TUDOMINIO";

echo "To install Magento, you will need a blank database ready with a user assigned to it."
echo
echo -n "Do you have all of your database information? (y/n) "
read dbinfo

if [ "$dbinfo" = "y" ]; then
    echo

    echo -n "Include Sample Data? (y/n) "
    read sample

    if [ "$sample" = "y" ]; then
        echo
        echo "Now installing Magento with sample data..."

        echo
        echo "Downloading packages..."
        echo

        wget http://www.magentocommerce.com/downloads/assets/1.3.2.3/magento-1.3.2.3.tar.gz
        wget http://www.magentocommerce.com/downloads/assets/1.2.0/magento-sample-data-1.2.0.tar.gz

        echo
        echo "Extracting data..."
        echo

        tar -zxvf magento-1.3.2.3.tar.gz
        tar -zxvf magento-sample-data-1.2.0.tar.gz

        echo
        echo "Moving files..."
        echo

        mv magento-sample-data-1.2.0/media/* magento/media/
        mv magento-sample-data-1.2.0/magento_sample_data_for_1.2.0.sql magento/data.sql
        mv magento/* magento/.htaccess .

        echo
        echo "Setting permissions..."
        echo

        chmod o+w var var/.htaccess app/etc
        chmod -R o+w media

        echo
        echo "Importing sample products..."
        echo

        mysql -h $dbhost -u $dbuser -p$dbpass $dbname < data.sql

        echo
        echo "Initializing PEAR registry..."
        echo

        ./pear mage-setup .

        echo
        echo "Downloading packages..."
        echo

        ./pear install magento-core/Mage_All_Latest

        echo
        echo "Cleaning up files..."
        echo

        rm -rf downloader/pearlib/cache/* downloader/pearlib/download/*
        rm -rf magento/ magento-sample-data-1.2.0/
        rm -rf magento-1.3.2.3.tar.gz magento-sample-data-1.2.0.tar.gz
        rm -rf index.php.sample .htaccess.sample php.ini.sample LICENSE.txt STATUS.txt data.sql

        echo
        echo "Installing Magento..."
        echo

        /usr/local/php5/bin/php -f install.php -- \
        --license_agreement_accepted "yes" \
        --locale "en_US" \
        --timezone "America/Los_Angeles" \
        --default_currency "USD" \
        --db_host "$dbhost" \
        --db_name "$dbname" \
        --db_user "$dbuser" \
        --db_pass "$dbpass" \
        --url "$url" \
        --use_rewrites "yes" \
        --use_secure "no" \
        --secure_base_url "" \
        --use_secure_admin "no" \
        --admin_firstname "$adminfname" \
        --admin_lastname "$adminlname" \
        --admin_email "$adminemail" \
        --admin_username "$adminuser" \
        --admin_password "$adminpass"

        echo
        echo "Finished installing Magento"
        echo

        exit
    else
        echo "Now installing Magento without sample data..."

        echo
        echo "Downloading packages..."
        echo

        wget http://www.magentocommerce.com/downloads/assets/1.3.2.3/magento-1.3.2.3.tar.gz

        echo
        echo "Extracting data..."
        echo

        tar -zxvf magento-1.3.2.3.tar.gz

        echo
        echo "Moving files..."
        echo

        mv magento/* magento/.htaccess .

        echo
        echo "Setting permissions..."
        echo

        chmod o+w var var/.htaccess app/etc
        chmod -R o+w media

        echo
        echo "Initializing PEAR registry..."
        echo

        ./pear mage-setup .

        echo
        echo "Downloading packages..."
        echo

        ./pear install magento-core/Mage_All_Latest

        echo
        echo "Cleaning up files..."
        echo

        rm -rf downloader/pearlib/cache/* downloader/pearlib/download/*
        rm -rf magento/ magento-1.3.2.3.tar.gz
        rm -rf index.php.sample .htaccess.sample php.ini.sample LICENSE.txt STATUS.txt

        echo
        echo "Installing Magento..."
        echo

        /usr/local/php5/bin/php -f install.php -- \
        --license_agreement_accepted "yes" \
        --locale "en_US" \
        --timezone "America/Los_Angeles" \
        --default_currency "USD" \
        --db_host "$dbhost" \
        --db_name "$dbname" \
        --db_user "$dbuser" \
        --db_pass "$dbpass" \
        --url "$url" \
        --use_rewrites "yes" \
        --use_secure "no" \
        --secure_base_url "" \
        --use_secure_admin "no" \
        --admin_firstname "$adminfname" \
        --admin_lastname "$adminlname" \
        --admin_email "$adminemail" \
        --admin_username "$adminuser" \
        --admin_password "$adminpass"

        echo
        echo "Finished installing Magento"

        exit
    fi
else
    echo
    echo "Please setup a database first. Don't forget to assign a database user!"

    exit
fi

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