Here is the scenario -
An ecommerce site. Thousands of "Sort by" pages (such as by Price, Type etc) and Pagination pages indexed. No Rel Canonical tag in place, but URL Parameters in WMT was set, with the option of "No URLs" for "Which URLs with this parameter should Googlebot crawl?"
I thought Google would not crawl and index these pages because of this directive, but it does. Three possibilities to my mind -
1. Add Rel Canonical tag and disable URL Parameters
2. Add Rel Canonical tag and keep URL Parameters.
3. Add Rel Canonical tag, keep URL Parameters and change it to "Let Googlebot decide" for "Which URLs with this parameter should Googlebot crawl?"
Any other line of attack that is better suited? Thank you