Background: We run a product aggregator site. We list 20k products which will grow to 200k within the next year and also have a section of the site where users can take those product images and create their own montages (this effectively allows users to create their own images).

We want to move the images to a storage server with a custom sub-domain/CDN e.g.

Move images from our existing domain:

  • https://www.example.com/content/product/product1.jpg (product image)
  • https://www.example.com/content/user/user1.jpg (user’s image)

to our custom sub-domain/CDN:

  • https://media.example.com/product/product1.jpg (product image)
  • https://media.example.com/user/user1.jpg(user’s image)

We are doing this for two reasons:

  1. It's a more cost-effective way to store images.
  2. We want to serve them up faster and speed up the site for the user.

Currently, we plan to keep a copy of the product images on our main domain (www.example.com/content/product/product1.jpg) but not the user generated ones.

We already have images indexed by Google and good traffic from it. We don't want to lose this traffic. But we also don't want to have duplicate images. Plus, if anyone links to the images on the sub-domain/CDN, we want to retain the 'link juice' to the main domain.

So, my questions:

  1. Regarding the product images, would it be best to use canonical headers from the CDN back to the main domain? (although this may mean moving to a CDN provider who offers canonical header redirects as our current provider doesn’t)
  2. Regarding the user generated images, these won't be available from our main domain, only from the CDN/storage sub-domain. So if anyone links to those CDN images directly, will our main domain benefit from the link juice?
  3. Our preferred method would be to 301 redirect the existing indexed images from our main domain to the new sub-domain/CDN, for example we would 301 redirect https://www.example.com/content/product/product1.jpg to https://media.example.com/product/product1.jpg. The only issue with this is again whether we are diverting possible link juice from our main domain over to a sub-domain?
  • As far as I know external links to your images don't help your site as a whole. They can make that particular image rank better in image search, but images don't in turn link to your other pages, so they don't help the rest of your site rank. – Stephen Ostermiller Aug 15 '18 at 11:50
  • As far as subdomains go, they aren't always bad for SEO. See Do subdomains help/hurt SEO? – Stephen Ostermiller Aug 15 '18 at 11:52
  • Thanks @StephenOstermiller. Have you ever seen the results of option 3, i.e. 301 redirects to a subdomain? If you have, did they receive an increase/decrease in ranking? – ela Aug 15 '18 at 21:21
  • I helped with 301 redirecting images to a media subdomain about 8 years ago on a large site. No web ranking problems. We didn't have much image ranking at the time though, so we didn't measure that. I wouldn't expect my experience from so many years ago to be all that relevant today. – Stephen Ostermiller Aug 15 '18 at 22:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.