Sitemap index errors: when one child file fails
An index can be valid while one child sitemap is broken. Check each child URL, status and size, and keep nested indexes and cross-host children out of the list.
The index is not the sitemap
A sitemap index only lists other sitemap files. Each child is fetched separately, so one failing child can leave the parent readable while part of the site disappears from the report.
Open the index and follow every child URL, not just the first one. The failing file is usually the one with a redirect, a 404, a login response, or an XML error.
curl -sL https://example.com/sitemap.xml -o index.xml
grep -o '<loc>[^<]*</loc>' index.xmlRules that catch people out
Child sitemaps must be on the same site as the index. A child that points to another domain will be rejected. Nested indexes are not supported: an index lists sitemaps, not another index.
Each child must be a valid sitemap in its own right and stay under the URL and size limits. A child that returns HTML, a compressed file the crawler cannot expand, or a partial response counts as a failure.
| Child observation | Meaning | Fix |
|---|---|---|
| Cross-domain child | Listed under the wrong host | Serve the child from the verified site |
| Nested index | An index inside an index | Flatten it into one level |
| HTML response | Route serves the app shell | Generate XML at that address |
| Timeout or 5xx | Child generation is slow or failing | Fix the endpoint and retry |
Keep the index small enough to diagnose
Group children by section, such as blog, products and tools. A smaller child is easier to test and isolates a failure to one part of the site.
Record the exact child URL that failed, the response, and the last-read time. After fixing it, fetch the child directly and then the index before resubmitting.
- One child per content type or directory.
- Test each child after every deployment.
- Keep child URLs stable; do not cache-bust them.
- Remove empty children rather than leaving 0-URL files listed.
Frequently asked questions
Can a sitemap index point to another index? No. Google does not support nested index files.
Do all children need to be on the same host? Yes. The URLs in a child must belong to the site the index was submitted for.
The index is readable but pages are missing. Check the child that contains those pages first; a single failed child is the usual cause.
Check the URLs inside the failing child
A free audit samples the pages you list, so a broken child is not mistaken for a content problem.
Run a free audit