Cloudflare Error 520: Meaning & Fix
Error 520 occurs when the origin server returns an unexpected response, empty, or unknown error to Cloudflare. By reading this guide, you will understand the causes of this error message and learn effective methods to resolve it.
What causes the Cloudflare error 502?
Error 520 typically arises when the origin web server fails to complete an incoming request, often due to crashes from resource-intensive scripts, firewall settings blocking Cloudflare IPs, short idle timeouts, or incompatible response headers. While not a direct cause, rate limiting can potentially contribute to this error.
How to get rid of Cloudflare Error 520?
Ensure Cloudflare DNS records are correct
Incorrect DNS records can lead to Error 520. Log in to your Cloudflare account and navigate to the DNS tab to verify that your DNS settings match those provided by your hosting provider. Ensure all A and CNAME records point to the correct IP addresses and that there are no conflicting or outdated entries.
Check headers and cookies
Excessive or malformed headers and cookies can cause the origin server to reject requests. Review your server's response headers for anomalies and ensure that the total size of request headers does not exceed Cloudflare's 16 KB limit. Simplify or remove unnecessary cookies to maintain compliance. Additionally, check for missing response headers, as they can contribute to failed requests and incomplete responses.
Use a proxy server to improve connectivity
Sometimes, the origin server may reject Cloudflare's requests due to IP restrictions. Using a proxy can help route traffic through different IP addresses, reducing the likelihood of blocked requests. If you're running a web scraper or bot, rotating, residential, or datacenter proxies can minimize the chances of triggering Cloudflare’s security filters. Additionally, reviewing your servers' error logs and the error log in your hosting panel can provide insights into failed requests and pinpoint configuration issues affecting your web page.
Web Scraper API to Avoid 520 Error
Say goodbye to data-gathering interruptions and focus on public data analysis with Oxylabs’ Web Scraper API. Using this API can help prevent triggering Cloudflare's security measures, ensuring uninterrupted data collection without making 520 errors occur.
Proxy management
Let ML-driven infrastructure handle proxies from a pool of 195 geo-locations for specific targets.
Custom parameters
Customize API behavior for your specific needs with custom headers and cookies.
AI-powered fingerprinting
Outsmart anti-scraping technologies with AI-picked IPs, headers, cookies, and WebRTC properties.
Automatic retries
Improve and simplify your processes with automatic retries of failed requests with different scraping parameters.
Headless Browser
Render JavaScript-reliant pages with a single code line and perform browser actions like clicking, scrolling, and more.
Custom Parser
Define custom parsing instructions and retrieve parsed data in JSON format.
Web Crawler
Crawl any site from top to bottom, select useful data, and fetch it in bulk.
Scheduler
Have your scraping projects run at any schedule, automatically deliver scraped data, and get notifications.