How do you avoid getting blocked when crawling?

Answer

To avoid getting blocked, crawl politely and predictably. Respect robots.txt, use reasonable rate limits, and identify your user agent. Add retries with exponential backoff instead of hammering the same URL. Keep concurrency low and randomize delays to reduce burst traffic. Watch for 429 or 503 responses and slow down when they appear. Consistent, light traffic is far less likely to trigger defenses.