If you‘ve ever tried to access or scrape a website and were met with a page that said "Error 1020: Access Denied", you‘ve encountered Cloudflare‘s bot protection. This can be extremely frustrating, especially if you were in the middle of collecting important data. But what exactly is Cloudflare error 1020, what causes it, and how can you avoid it to scrape websites successfully?
In this in-depth guide, we‘ll cover everything you need to know about Cloudflare error 1020 and share proven techniques to prevent it from blocking your web scraping efforts. Let‘s dive in!
What is Cloudflare Error 1020?
First, it‘s important to understand what Cloudflare is. Cloudflare is a popular service that many websites use to improve security, performance, and reliability. One key feature is its firewall and DDoS protection which analyzes incoming traffic and blocks suspicious requests.
When Cloudflare detects that a request has violated one of the website‘s firewall rules, it blocks the request and returns a 1020 "Access Denied" error. This is Cloudflare‘s way of protecting websites from malicious bots, DDoS attacks, content scraping, and other unwanted automated traffic.
The full error message you‘ll see is:
"Access denied
Error code 1020
What happened?
This website is using a security service to protect itself from online attacks."
What Causes Cloudflare Error 1020?
There are a number of reasons why your request might get blocked with a 1020 error, but it generally means Cloudflare flagged it as automated or potentially malicious. Some common causes include:
- Sending too many requests too quickly (high rate of requests)
- Not using legitimate user headers (user agent, cookies, referrer, etc.)
- Your IP address has a bad reputation associated with bots/spam
- The page requires Javascript rendering but your bot doesn‘t run JS
- You‘re trying to access a restricted area (login page, admin panel, etc.)
- The site owner has configured strict firewall rules that your request triggers
Basically, if your requests don‘t sufficiently resemble normal user traffic from a web browser, there‘s a good chance they‘ll get blocked. Cloudflare‘s bot detection is quite sophisticated.
How to Fix Cloudflare Error 1020
So you‘re trying to scrape a site but keep running into the dreaded 1020 error. How do you resolve it so you can continue collecting data? Here are some tips and best practices.
1. Check if the site is reachable normally
Before attempting to circumvent the bot protection, first double check that you can reach the site in a normal web browser. If you get the same Access Denied message, then the issue isn‘t your scraping tool but rather a network or connectivity issue on your end.
Try accessing the URL in an incognito browser window. If that also doesn‘t work, the site may actually be down or blocking your IP. Try a different network or VPN.
2. Slow down your request rate
One of the most common reasons for bot detection is simply sending requests too frequently. Rapidly bombarding a site with page requests in a short time span is a sure way to get blocked.
Add delays between your requests to better simulate human browsing behavior. A few seconds is usually good but for very bot-sensitive sites you may need 10+ seconds between requests. Experiment to find the sweet spot.
3. Rotate IP addresses and user agents
Another big red flag is when all requests come from a single IP address. Normal users have diverse IPs.
Use a pool of proxy servers to rotate the IP address on each request. Ideally these should be premium proxies with a good reputation. Rotating data center IPs may still get blocked. Residential proxies from real devices are best for avoiding IP-based blocking.
Also make sure to set a valid, rotating user agent header to represent different browsers/devices.
4. Use human-like headers and cookies
Take a look at the headers a real web browser sends when accessing the site. Try to replicate those as closely as possible in your scraper.
In particular, set:
- A common user agent string
- Referrer URL
- Language and encoding
- Any cookies the site sets
You can use browser dev tools or an extension to view the full headers. Replicate all the standard ones.
5. Handle Javascript rendering
Some sites use Javascript challenges and CAPTCHA pages that require JS rendering to solve. If your scraper doesn‘t execute JS, you won‘t be able to progress.
Tools like Puppeteer or Selenium can render pages in a full browser environment. For JS-heavy sites, you‘ll need to use a rendering tool vs a simple HTTP library.
6. Mask your scraper as a normal browser
For the stealthiest approach that is very difficult to detect, consider using an automated browser profile that masks itself as a human user.
Undetected-chromedriver is a popular Python package that automatically configures Chrome to avoid triggering bot detection. It takes care of headers, cookies, WebGL fingerprinting, and many other advanced checks.
Combining undetected-chromedriver with residential proxies is a great way to make your scraper requests seem like normal user traffic to Cloudflare‘s systems. It requires more resources than simple requests but is very effective for avoiding 1020 errors.
Use ScrapingBee to Avoid Blocks for You
Finally, if you want to avoid dealing with Cloudflare‘s bot protection yourself, you can let a dedicated web scraping API handle it.
ScrapingBee is a powerful tool that takes care of IP rotation, headers, browser rendering, and CAPTCHAs behind the scenes so you can just focus on parsing data. It manages a large pool of proxies and browser profiles to keep your requests undetected.
With the ScrapingBee API, you simply provide the URL you want to scrape and get back the HTML response. It acts as a smart proxy to retrieve the page content for you, handling any anti-bot measures along the way.
Here‘s a quick example of using the ScrapingBee Python SDK:
from scrapingbee import ScrapingBeeClient
client = ScrapingBeeClient(api_key=‘YOUR_API_KEY‘)
response = client.get(
‘https://example.com‘,
params = {
‘render_js‘: ‘false‘
}
)
print(‘Response HTTP Status Code: ‘, response.status_code)
print(‘Response HTTP Response Body: ‘, response.content)As you can see, with just a few lines of code you can retrieve the page HTML without worrying about Cloudflare blocks. The API takes care of retrying failed requests and returning the content as if a real browser user accessed it.
Using a specialized scraping API saves a lot of time and headache vs trying to make your scrapers undetectable yourself. Give it a try if you want the simplest way to avoid 1020 errors.
Wrap Up
Cloudflare error 1020 can definitely disrupt web scraping efforts, but with some adjustments to your approach it‘s possible to avoid it in most cases. Remember these key tips:
- Slow down your request rate to mimic human behavior
- Rotate IP addresses and headers to diversify traffic
- Use human-like browser headers, cookies, and user agents
- Handle Javascript rendering for JS-based challenges
- Consider a scraping API like ScrapingBee to abstract away blocks
With the right techniques and tools, you can collect data from even the most bot-sensitive sites without triggering Cloudflare‘s defenses. The key is making your scraper act as much like a real user as possible.
I hope this guide has been helpful for understanding and solving Cloudflare error 1020! Let me know if you have any other questions.
