#package installation
    sudo apt-get update
    sudo apt-get install libssh2-php
#mysql-settings
    define('DB_NAME', 'wordpress');
    define('DB_USER', 'wordpress');
    define('DB_PASSWORD', 'password');
#make-backup
    mysqldump -u wordpress -ppassword wordpress > /home/user/wodpress.sql
    tar -czvf www.tgz /var/www/
#update-setup
    #wp-user
        sudo adduser wp-user
        cd /var/www
        sudo chown -R wp-user:wp-user /var/www/
    #ssh-keys
        sudo su - wp-user
        ssh-keygen -t rsa -b 4096 /home/wp-user/wp_rsa
        exit
        chown wp-user:www-data /home/wp-user/wp_rsa*
        chmod 0640 /home/wp-user/wp_rsa*
        mkdir /home/wp-user/.ssh
        chown wp-user:wp-user /home/wp-user/.ssh/
        chmod 0700 /home/wp-user/.ssh/
    cp /home/wp-user/wp_rsa.pub /home/wp-user/.ssh/authorized_keys
        chown wp-user:wp-user /home/wp-user/.ssh/authorized_keys
        chmod 0644 /home/wp-user/.ssh/authorized_keys
        vim /home/wp-user/.ssh/authorized_keys
            from="127.0.0.1" ssh-rsa...
    #wp-config
        vim /var/www/wp-config.php
            define('FTP_PUBKEY','/home/wp-user/wp_rsa.pub');
            define('FTP_PRIKEY','/home/wp-user/wp_rsa');
            define('FTP_USER','wp-user');
            define('FTP_PASS','');
            define('FTP_HOST','127.0.0.1:22');
            define('FS_METHOD', 'ssh2'); # - important

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