My website has undergone many changes over the past 10 years, as I guess most have, rankings have dropped and over the past few months I have been working on the site and CMS a lot to improve it, but this has a raised a couple of points of discussion...
I have posted another question too which is related, but separate.
How best to handle product variations
My CMS system creates individual product records in the database for every product variation, but links them by title. So, for example: https://www.onlineguitarsales.co.uk/Product/Rotosound-Nickel-Plated-Electric-Guitar-Strings-Purple-Heavy-12-52-p1973 is a packet of Rotosound Electric guitar strings, 12 gauge. There is a drop down list from which you can chose different gauges (the variation on this particular product is gauge, obviously some it's colour, style, size, etc, etc). The "parent" product in the database is https://www.onlineguitarsales.co.uk/Product/Rotosound-Nickel-Plated-Electric-Guitar-Strings-Light-Pink-9-42-p1420.
Although the CMS system creates separate product records for each one, it internally duplicates the descriptions, specifications etc of each variation (there is an option to override this, but we'll ignore that for now), allowing only the Variation Description and the pictures to be different.
Naturally, if each individual page was presented to Google, this would immediately create duplicate content issues.
To overcome this, we have a
rel="canonical" tag on each of the variant pages pointing to the "Parent" product, eg, see the
<head> tags for the first link above and you will note it contains a
rel="canonical" tag referencing the second.
Having read lots on Stack Exchange, SEO Moz, Google, etc, etc, I feel fairly safe that this is the right way to go.
My question is: Should I also add
<meta name="robots" content="NOINDEX, FOLLOW"> tags to the variation (non-parent) pages?