SEO Implications For a Technical Functionality Fix

[19prince]

Our Magento based affiliate extension is not working, due to a conflict with the Varnish caching system. Varnish has a known bug which does not allow multiple cookies to be set.

Our workaround involves redirecting any request with the affiliate tracking parameter to the HTTPS version of the site. Varnish does not run on HTTPs and therefore our affiliate cookie will be set. Note: the main content of our site runs on HTTP.

My SEO concern is how to handle this for the search engines. We have a few things to consider:

1. Redirect: Should we use a 301 or 302?
2. Canonical: It seems to make sense to include a canonical on the HTTP version of the site without the affiliate tracking parameter - right?
3. Robots Meta Tags: "noindex, follow" or "index, follow"
4. Am I missing something?

Thanks for your time and consideration!

[19prince]

Thanks again to Ryan and Cyrus for chiming in. I'm going with:

• noindex,nofollow all HTTPs pages (they're not in the index anyway)
• Pull canonical tags from all HTTPs pages
• 301 redirect affiliate id links to HTTPs version of the page

Now, I just need to remember all of this when we finally get to transferring the site fully to HTTPs.

[19prince]

Thanks for the thoughtful reply.

[RyanPurkey]

Excellent and thorough breakdown by Cyrus here Darren. I didn't consider the nofollow / noindex combination negating the need for canonical because I was thinking of the incoming affiliate links to be nofollow to begin with (links form outside your site).  I was also thinking nofollow / follow conflicts might arise on your HTTP site due to their presence on the HTTPS pages depending on how your site is constructed (inside your site).  But now you've got analysis on the many angles you should be set to make an informed decision either way. Cheers!

[Cyrus-Shepard]

If I understand correctly, you have incoming affiliate links which don't work on HTTPs due to varnish, so you are redirecting them to HTTPs, where they do work. Let me know if I'm missing anything.

Okay, first of all if you are serving up two versions of your site on any page (HTTP and HTTPS) without 301'ing one to the other, you should absolutely have canonical tags pointing to the HTTP. And without the affiliate tracking parameter.  (Edit: see thoughts below on NOINDEX)

As for 301 vs 302: Technically, to stay within Google's guidelines, affiliate links to your site should be nofollowed. In practice, sometimes they can offer a ranking benefit, but more than often Google discounts them. Regardless, if you abuse them for linking purposes it can come back to bite you in some instances. There's no clear answer, but keep in mind 302s may very well negate some of the link equity from these affiliate links (which may or may not be a good thing)

NOINDEX - My thought process is, if you don't want the HTTPS URLs indexed, and the link equity from the affiliate links isn't a consideration, then it's likely best to NOINDEX, NOFOLLOW the pages. This ensures they will be kept out of Google's index, keep crawl efficiency optimized, and deliver cleaner results. This also means the canonical tag isn't necessary. (and probably unwanted, as it sends conflicting signals with the NOINDEX tag) Keep in mind this strategy effectively kills any incoming link equity from the affiliate links, but does help keep you within Google's good graces.

[RyanPurkey]

I don't see a downside to the 302 as it seems like the best one to use in this case. Similarly Google recommends a 302 for pages that are alternate language copies of each other, so it's a well-established convention to redirect in that regard, "A third scenario would be to automatically serve the appropriate HTML content to your users depending on their location and language settings. You will either do that by using server-side 302 redirects or by dynamically serving the right HTML content." from http://googlewebmastercentral.blogspot.com/2014/05/creating-right-homepage-for-your.html.  In your case the location and language portion is being replaced with affiliate tracking variable.

[19prince]

Thanks for the time.

RE: HTTPs the entire site.  Varnish doesn't play too nice with HTTPs. Plus, my understand is that one's site may take a performance hit...The whole reason we went to Varnish was due to perforance.  BTW...the site is now pretty fast.

RE: 302. Just wondering if there are any down side...

[RyanPurkey]

Hi Darren. If you can, you could also consider migrating the entire site to HTTPS and using the 301 redirect. Otherwise a 302 would be more applicable as it's a conditional redirect for the page, based on the affiliate tracking parameter. With the 302 and HTTPS configuration, you'd also want to additionally set canonical to the HTTP version as that's the more publicly available site, and one you'd expect crawlers to go to minus the affiliate link.  In this case it also sounds like the page is going to almost an exact duplicate, so noindex would be wise as well since you don't want search traffic landing on HTTPS as they're not an affiliate visit.  That covers most of it. It sounds like you've already read what's out there, but here's Google's guide on using HTTPS: https://support.google.com/webmasters/answer/6073543. Cheers!