IP Addresses tell websites what device is trying to access them from the internet or a local network. Companies, therefore, must be careful regarding how they put IP addresses to use. If a website suspects someone might be using an IP Address for nefarious purposes, it could put it on a blacklist, which impacts an organization’s ability to collect data from online platforms.

That’s why it’s essential to understand what an IP blacklist is, how it works, and how to unblock an IP address if it ever gets flagged.

The Importance of IP Addresses

Getting anything done on the internet is hard without a legitimate IP address. IP addresses play a fundamental role in online communication. Every time someone sends or receives data on the internet, that data gets broken down into packets. Identifying devices on the internet is crucial for accurately routing those data packets to their intended destination.

Sending an email, participating in a video work call, or using a messaging app all require an IP address to connect devices. An IP address is also needed to implement network security measures. Firewalls, intrusion detection systems, and other security tools review IP addresses to determine whether incoming traffic comes from a legitimate or harmful source. Organizations track IP addresses to identify potential malicious activity.

In fact, servers with IP addresses host websites. For example, after a user enters a domain name like www.amazon.com into a web browser, a Domain Name System (DNS) translates the information into a specific IP address. Web browsers then use IP addresses to locate and retrieve content from the correct server.

What Is an IP Blacklist?

Many websites safeguard themselves from IP addresses known for hacking and data theft. They do so by flagging IP addresses as illegitimate and putting them on so-called blacklists.

IP blacklists, also known as blocklists or reputation lists, compile IP addresses identified as participating in malicious or undesirable internet activities. Examples include sending multiple spam emails, distributing malware to execute a cyber-attack, and hacking attempts.

Web scraping can also get you on an IP blacklist. That’s because Web Scraping tools automatically extract information from websites. While that may not be a malicious act itself, many websites view the repetitive attempts to collect data as a potential attack.

Organizations relying on web scraping must, therefore, figure out how to unblock an IP address if it ever gets flagged while collecting data.

Reasons for web scrapers ending up on an IP blacklist

Here are some of the reasons why those using web scraping might find themselves looking up how to unblock an IP address after unexpected blacklisting:

• Aggressive scraping — Scrapers send excessive requests to a website within a short period, straining the website’s resources and disrupting normal functions. This behavior can trigger security mechanisms to block the IP address that is causing the issue.
• Request frequency — If a web scraper doesn’t have a delay between requests, called rate limiting, the numerous requests can flood website servers, which can appear similar to a distributed denial-of-service (DDoS) attack.
• Not following robots.txt instructions — Most websites contain a “robots.txt” file that tells engines and web scrapers which pages are accessible for crawling and which ones to avoid. Scrapers that ignore the instructions can trigger alarms that lead to blacklisting.
• Mass data extraction — Extracting massive amounts of data in a short period can also lead to an IP block.
• User-agent spoofing — Scrapers can mimic human behavior by changing user-agent strings to appear as different browsers. If not done correctly or in excess, a website might view those alterations as an attempt to evade detection.
• Search/request errors — Security measures can assume that web scrapers that constantly request non-existing or restricted pages try to probe for vulnerabilities. That can lead to IP flagging and the need to figure out how to unblock the IP address.
• Pattern detection — Websites and security systems often analyze web traffic patterns. They often flag any unusual activity, like sequential requests or requests for data-heavy resources, as unwanted. These websites then ban the IP address from taking further actions, meaning companies must figure out how to unblock an IP address to continue using it.
• Geographical mismatch — Web scrapers using IP addresses from a different region or country may be viewed as suspicious by a website.
• Content duplication — Scrapers may get on a blacklist for copying website content without permission or attribution. That type of unethical behavior could lead to organizations having to work through unblocking an IP address.

Limitations of blacklists

IP blacklists help companies protect their online platforms by locating and mitigating threats. However, some limitations impact their effectiveness and accuracy:

• False positives — Blacklists sometimes flag legitimate IP addresses because they use shared IP spaces or other data collection processes reuse them. When that happens, non-malicious actors must find how to unblock their IP addresses.
• False negatives — Malicious actors can evade detection by employing proxies or using dynamic IP addresses. The threats can go unnoticed because a blacklist might not capture those instances of unusual behavior.
• Evolving landscape — New threats emerge constantly within the digital landscape. Because of that, blacklists may struggle to keep up with the creation of new malicious IP addresses. IP blacklists typically focus on known threats. New or advanced threats may not fit existing patterns, meaning they can bypass getting detected.
• Geolocation challenges — Blacklists that operate based on location often assume that every IP address from a specific geographical region is malicious. That can lead to incorrect assumptions and cause blocking of legitimate IP addresses.

Because of these factors, many companies using IP addresses for legitimate purposes may find themselves searching the steps on how to unblock an IP address.

Types of IP Blacklists

In addition to websites, organizations employ IP blacklists to protect other online platforms, email servers, and firewalls. Below is an overview of the different blacklists in use:

Public

Organizations keep openly accessible IP address lists to make it known that the addresses included are known for conducting malicious activities.

Private

Some organizations maintain internal blacklists not accessible to the public to control who has access to their resources.

Commercial

Some blacklist curation companies, like Invaluement and MxToolbox, earn on maintaining blacklists for other organizations. Businesses use them as a resource for enhancing cybersecurity measures. For example, threat intelligence platforms (TIPs) use blacklists as one of many sources for identifying and blocking threats.

Reputation-based

These blacklists assign IP addresses a reputation score based on their behavioral history. A poor reputation score can lead to blocking.

For example, a blacklist with a score range of 1-100 might assign an 83 to an IP address with a good reputation. However, an IP address known for constantly overloading website servers via a web scraper might receive a low score of 23, limiting the robot’s ability to perform its designated information collection tasks.

How Do IP Blacklists Work?

Below is an overview of the typical methods blacklists use to block or filter any IP address they deem suspicious or undesirable. Understanding these general mechanisms can help businesses determine how to unblock an IP address or avoid a blacklist entirely.

1. Data collection and analysis

Organizations start crafting their blacklists by collecting data from sources like network traffic analysis, user reports, and honeypots, which are all decoy systems designed to appeal to attackers. Collected data includes information about IP addresses involved in practices like malware distribution, spamming, and hacking attempts.

2. Evaluation

Organizations then review all collected data to determine if an IP address actually engaged in any malicious activities or exhibited behavior that poses a threat. They may assign a reputation score based on the IP address’s historical activity patterns. The higher the reputation score, the less likely the IP address was doing anything unethical or illegal. Low scores can result in a company needing to work through steps on how to unblock an IP address.

3. List Creation and Maintenance

After evaluating the data, companies categorize IP addresses into different blacklists. These blacklists receive constant updates based on the changing online landscape and new threats. Therefore, companies may remove any IP address showing improved behavior from the blacklist, so flagged users don’t need to go through the steps on how to unblock an IP address repeatedly.

How Can You Tell If an IP Address Is Blocked?

Businesses can check whether their IP addresses are on public blacklists through tools such as Blacklist Check or DNS Checker. If you find your designated IP address on one of these sites, you’ll need to figure out how to unblock the IP address.

If you have multiple IP addresses to verify, searching them one by one via a website can be impractical. Some other methods of determining the state of your IP addresses include the following:

1. Examining network traffic patterns

Businesses can review their network traffic logs and look for unusual patterns or a sudden uptick in errors. They can also look for an increase in HTTP status codes that indicate an IP blocking, including:

• 403 – Forbidden
• 429 – Too Many Requests
• 503 – Service Unavailable

2. Checking for Error Responses

You can also check for error responses from target websites during web scraping. Pay attention to any previously successful responses that suddenly start returning errors.

3. Spotting Unusual Scraping Behavior

If your web scraping processes start behaving unusually or not working as programmed when pulling data from a web page, that could indicate changes in layout or structure. It could suggest that the owners changed the website in response to web scraping.

If your web process continues exhibiting unusual behavior, the IP address could get flagged. That means you will need to work out how to unblock the IP address.

4. Detecting Email Issues

Some companies tie their web scrapers to other email marketing or outreach processes. One way these businesses can determine if there are issues with an IP address is by checking whether emails are getting marked as spam or not getting delivered.

Many email servers use blacklists to search for suspicious IP addresses. Your IP address ending up on a blacklist could be the root cause of your email issues. In that case, you will need to work through unblocking an IP address.

How Can You Remove an IP Address From a Blacklist?

Below is a general overview of how to unblock an IP address, although the process may vary depending on your device, server, and other similar factors:

1. Locate the blacklist

Whether you’re looking at how to unblock your IP address on your phone or computer, the first step will be the same for every device used. Look for any blacklists upon which your IP address appears by searching public online platforms that curate IP blacklists. It’s a good idea to search multiple public blacklists to see if your IP address comes up.

2. Check for the blacklist reason

Try to find a reason for your IP address ending up on a blacklist by reviewing your web tracking logs. This will help you determine if a web scraping solution is malfunctioning.

Any unusual movements can appear to websites as taking malicious or suspicious actions. Technical issues can also trigger blacklisting, which you must resolve before unblocking an IP address.

3. Look for a resolution

Focus on finding a solution to the core reason for blacklisting. If it was because of unusual or suspicious activities, check your systems’ security and make any necessary changes to resolve the issue. If a web scraping process is overloading website servers, add a delay between each request. Also, try rotating IP addresses to prevent too many requests from a single IP address.

If you’re having difficulty with certain web fonts, extensions, or JavaScript coding, try using a headless browser, one that does not have a graphical interface. That helps your web scraping process appear more human to websites. Once you find a reason and the solution, you can move forward to the next steps on how to unblock an IP address.

4. Review delisting policies

Contact the website support team that placed the IP address on a blacklist. You can also check the company’s delisting policies, procedures, and guidelines for requesting the unblocking of an IP address.

5. Submit a delisting request

The website provider’s delisting procedures will guide you on the best method to use for unblocking your IP address. You may need to fill out a form, send an email, or visit an online portal to submit a request to unblock an IP address.

Include evidence that the blacklisting was a mistake or that you’ve resolved the issue that led to the action. You may need to provide information about your logs, documentation of corrective actions taken, and detailed explanations of how the problem occurred.

After submitting the request to unblock an IP address, the website provider will review it. How much time it takes can vary based on their workload. Send a follow-up if you feel the process is taking too long.

8 Best Practices for Avoiding IP Blacklists When Web Scraping

The best way to avoid having your legitimate web scraping solution on an IP blacklist is to follow ethical and practical web scraping processes. Here are the eight best practices you can employ right now:

1. Follow “robot.txt” guidelines

Look for the “robots.txt” file, typically located directly at a website’s root. A “robot.txt” file contains a user-agent line specifying rules to which scrapers must adhere. For example, you may find a line that applies specifically to Google or Bing crawlers.

You should also check for “Allow” and “Disallow” directives outlining which website parts are allowed or prohibited for scraping. Some “robot.txt” files contain a crawl delay directive specifying how long crawlers must wait before submitting a new request. Respecting the delay allows web scraping processes to appear more human-like, avoiding the need of having to unblock an IP address.

2. Use a scraping framework

Look for existing web scraping frameworks and libraries already incorporating IP management best practices like rate limiting and human-like scraping behavior. Scraping frameworks typically come with features that simplify user-agent management. That allows businesses to emulate different web browsers or user agents to avoid detection and blocking.

Many frameworks also provide built-in support for IP rotation and proxy integration. Both are important in helping a web scraping robot avoid IP blacklisting. They distribute requests evenly across multiple IP addresses, which lowers the risk of blocking.

3. Apply rate limiting

Rate limiting helps organizations control the frequency and volume of requests sent to a website’s server. Businesses should base the rate on the website’s instructions and server capacity. For example, if you are only supposed to send ten requests per minute, wait 6 seconds between each request, equaling ten requests every 60 seconds.

In addition to rate limiting, add delays to help web scraping solutions mimic human behavior. An example would be adding a random delay value of four to eight seconds to each request. Apply these techniques in the web scraping code, using loops and other iterations to ensure each request follows the specified delay.

4. Rotate IP addresses

IP address rotation involves changing the location of an IP address either at different intervals, after making a certain number of requests, or during every internet connection. Cycling through multiple IP addresses distributes the load from web scrapers, reducing the chances of a website adding an IP address to a blacklist.

Businesses can obtain a pool of IP addresses by working with a provider that offers proxy servers or IP rotation services. With a collection of IP addresses, every address represents a unique internet entry point. After each request, a new IP address gets selected from the pool and used for the following action.

5. Monitor server responses

Always check the monitoring logs for HTTP status codes that indicate the outcome of each web scraping request. If you see status codes like 200, your web scraping solutions operate as intended. Otherwise, there may be a problem that leads to IP blocking. That will force you to learn how to unblock the IP address.

In addition, organizations should check the response content to ensure they receive the expected information. The content should match the structure and format outlined for your robots to follow. Keep track of server response times, as slow times can indicate potential server overload and other performance issues.

6. Handle CAPTCHA challenges

Many websites employ third-party services that place automated CAPTCHA problem-solving to prevent automated processes from accessing their data. Headless browsers can help web scraping processes get around CAPTCHA by simulating human interactions.

Other ways of getting around CAPTCHA challenges include implementing a delay-and-retry strategy by waiting a specific time before retrying a request. You can also try updating user-agent strings in requests to bypass CAPTCHA challenges. Otherwise, you can end up having to unblock an IP address after failing CAPTCHA.

7. Avoid aggressive scraping

In addition to implementing delays, sending randomized requests can mitigate having your robots perceived as aggressive web scrapers. Try to limit the sending of concurrent responses from one IP address. If you overload a server with simultaneous responses, your web scraping process can get an unwanted flag.

Avoid collecting more information than needed to keep your requests from straining a website’s servers. Otherwise, you can trigger a flag and end up having to learn how to unblock an IP address.

8. Adapt to website changes

You should constantly monitor target websites for any changes. Detecting changes early gives you more time to adjust web scraping solutions to handle the new format. You may also want to set notifications in your web scraper that provide alerts about changing website elements.

Use XPath expressions and CSS selectors to find page elements. Those tend to be more change-resilient than fixed-element positions. Some websites use JavaScript to load content dynamically. If your web scraping process encounters such a site, employ a headless browser to get information that may not be present in the HTML source.

Use a fallback mechanism on any website elements subject to frequent changes. You should perform regular maintenance on web scraping solution scripts to ensure they remain functional and accurate. Test any changes to your web scraping solutions locally on a small scale before deploying them for broader use. Otherwise, issues with parsing website code can lead to an IP ban and the need to unblock an IP address.

Final Thoughts

Ending up on an IP blacklist while conducting legitimate web scraping can cause an array of inconveniences for your company. You could face delays in your operations and waste precious time and money.

To avoid landing on one such list and having to unblock your IP address, ensure you upgrade your data collection processes to work more efficiently. Consider also working with a provider capable of delivering legitimate, verified IP addresses that aren’t on blocklists. Adhering to web scraping best practices can further help bring legitimacy to your online operations.

Rayobyte provides IP solutions that help businesses establish ethical and efficient web scraping. We offer verified IP addresses that organizations can use for efficient data collection processes while avoiding the entire hassle of unblocking an IP address. Contact us today to learn more about our products.

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