Simple way to create DB backups in Craft CMS 2.
Install the plugin and set a key in the settings.
Simply create a GET or a POST request to the action url.
In a template:
{{ siteUrl(craft.config.get('actionTrigger') ~ '/dump/backup', { key: '1234567890' }) }}
Or create the url yourself: http://www.domain.com/actions/dump/backup?key=1234567890