Non-Indexable Canonical
What This Means
Pages with a canonical URL specified that is non-indexable. This will include canonicals which are blocked by robots.txt, no response, redirect (3XX), client error (4XX), server error (5XX), are ‘noindex’ or ‘canonicalised’ themselves. This means the search engines are being instructed to consolidate indexing and link signals to a non-indexable page, which often leads to them ignoring the canonical, but may also lead to unpredictability in indexing and ranking.
What Triggers This Issue
This issue is triggered when pages have a canonical URL pointing to a non-indexable location. This includes canonical URLs that are blocked by robots.txt, have no response, redirect (3XX status codes), client error (4XX status codes), server error (5XX status codes), are marked as ‘noindex’, or are themselves canonicalised to another URL. For example:
https://www.getasky.com/ Has the canonical:
<link rel="canonical" href="https://www.getasky.com/froggy/"> But https://www.getasky.com/froggy/ is blocked in the robots.txt.How To Fix
Ensure canonical URLs are to accurate indexable pages to avoid them being ignored by search engines, and any potential indexing or ranking unpredictability.