This translation has not been editorially reviewed yet. The German version is authoritative. Deutsche Fassung
Indexing
What is a Canonical Chain and Why Does Google Ignore It?
With a canonical, a page says: The authoritative version of this content lies under that address. Search engines follow the hint — but only one step far. If the target in turn points to a third address, a chain is created and Google treats the indication as unreliable. If the target no longer provides content, but an error or a forwarding, the page points to something that cannot be indexed. The test area indexing follows the canonical of the tested page and reports both: chains and broken targets.
What the probe does
If the checked page references another address via canonical, the probe retrieves this address and follows forwardings. If the final destination does not provide a status 200, the result is the address and status: The canonical points into the void. If it delivers 200, the probe reads its canonical; Pointing it to a third address, this is the chain, and the finding calls both links. If the page points to itself or does not have a canonical, the probe does nothing – the absence evaluates the own canonical rule of the test area SEO. The result does not change the point value because the set of rules idx-v1 remains unchanged; it appears in the report and in the task list.
How chains are created and how to dissolve them
Chains are almost always created by moving: The website changes from http to https or from www to without www, old canonicals remain, and the new version sets its own canonical. Or an article is moved, the old canonical still points to the intermediate station. The resolution is mechanical: each canonical points directly to the final address, and the final address points to itself. Editorial systems usually generate canonicals automatically from the current address; then it is enough to check the template and remove old overwrites. After the correction, the test area no longer shows a result on the next run.
- Open the canonical destination of your most important pages in the browser and check status code and its own canonical.
- Put Canonicals directly on the final address — including https and the chosen www spelling.
- After a move, remove manually placed canonicals that still point to intermediate stations.
- Have the Canonicals editorial system generated automatically and check the template once instead of each page.
