Google advises sites to return 503 status codes instead of 404s when patching PHP to preserve indexation

Google advises serving 503 status codes from outside PHP during patches and keeping robots.txt accessible to prevent URLs from being dropped from the index.

Google's Gary Illyes and Chery Prommawin released a video explaining which robots.txt directives are actually supported by Google and other search engines or AI crawlers.

John Mueller provided guidance on maintaining search visibility when temporarily taking a site offline to patch the PHP2Shell vulnerability.

Google updated its help docs to explicitly list existing data-sharing controls including robots meta tags, data-nosnippet, X-Robots-Tag, and Search generative AI controls.