Examining server or infrastructure logs to understand requests, response codes, crawler activity, and access problems.
Log file analysis examines records of requests handled by a server or other infrastructure. Depending on the system, records may include a requested path, timestamp, response code, transferred bytes and a claimed user-agent. This can help answer which URLs were requested and what responses were returned, rather than relying only on what a page looks like now.
The available evidence depends on where the log was collected. A content-delivery network may serve a cached response without contacting the origin server, so an origin log is not necessarily a complete record of every visit. Fields, retention periods and time zones also vary. Establish that scope before treating a missing entry as proof that no request occurred.
Crawler identification needs care. A user-agent string can claim to be Googlebot without proving that the request came from Google. Use the search engine’s documented verification method when identity matters. A verified request also does not prove that the page was indexed or that a customer saw it in search; logs describe requests, not every downstream outcome.
Takeaway: Use logs to investigate specific access and response questions. Keep the collection layer, time range and identity-verification limits attached to your conclusions.
Example
A supplier receives reports that an old product URL fails intermittently. Its developer compares the relevant requests and response codes around the reported times, then checks the delivery layer that handled them. The investigation is narrower and more useful than assuming a current successful reload proves there was never a problem.
What to check
Ask for only the records needed for the diagnosis and handle them securely. Logs can contain IP addresses, query parameters or other sensitive details. Do not publish a raw log as an SEO report; summarize the relevant evidence and restrict access to the underlying records.
For more detail, see Apache HTTP Server logging documentation.