Because many people do not know enough about proxy IP, they always think that with proxy IP, crawling will not be limited, and they can always work steadily and continuously. However, the reality is that the crawler proxy IP will often be unable to access the public data, and the crawler work will be interrupted. So, what are the reasons why crawler proxy IP can't access public data?
1. Non-high secret proxy IP
In the process of using proxy IP, non-high secret proxy IP is a type that requires extra vigilance. Such proxy IP includes transparent proxy IP and punic proxy IP, which have some obvious limitations and problems in protecting user privacy and maintaining the stability of crawler work.
Transparent proxy IP, as the name implies, reveals the real IP address of the client. When the crawler uses the transparent proxy IP, the target website can directly obtain the user's real IP, which is easy to attract the attention of the website. Webmasters may treat these requests as normal user visits, but if the frequency of requests is too high, it is likely to be judged as abnormal behavior, which can result in IP blocking or restricted access.
The punic proxy IP hides the real IP address of the client, but still reveals that the proxy is used. In this case, although the target website cannot directly obtain the real IP, it can still sense the presence of the proxy, thus causing alarm. If the Punic proxy IP is frequently used in the crawling process, the website may consider this to be an abnormal crawling behavior and take restrictive measures, which will affect the data acquisition.
Second, the request frequency is too high
The nature of crawler tasks is to obtain a large amount of data, and completing the task in a limited time often becomes a challenge for engineers. In the pursuit of efficiency, sometimes we may overlook the importance of request frequency. Request frequency, that is, the number of requests initiated per unit time, is a key factor affecting the stability of proxy IP usage.
In crawler work, setting the request frequency too high may cause excessive load on the target website server. When a large number of requests flood the server in a short period of time, the processing capacity of the server may exceed the load, affecting the normal operation of the website. In such cases, webmasters often take protective measures, perhaps limiting the number of times a single IP address can be accessed, or simply blocking the corresponding IP address to protect the stability of the server.
3. Ask regularly
Some crawlers may not be designed with sufficient consideration for the randomness of requests, resulting in each request taking the same amount of time, with regular request intervals. In this case, it is easy for the target website to recognize this abnormal behavior and take restrictive measures.
4. Too many requests for a single IP address
Even in the case of high-hiding proxy IP, too many requests from a single IP in a short period of time can be a factor that attracts the attention of the target website. Many websites have restrictions on the frequency of access, which are designed to protect server resources from abuse, but can also cause proxy IP to be restricted or blocked when trying to access public data, which is one of the common reasons why proxy IP can't get data.
In the modern network environment, webmasters usually take a series of measures to monitor and manage the user's access behavior, including monitoring the request frequency of a single IP. Once an IP initiates too many requests in a short period of time, the system flags this as abnormal behavior, which may temporarily or permanently restrict access to the IP. This strategy helps to protect the stability of the site and data security, but for normal crawling tasks, it can cause unnecessary distress.
5. Other reasons
Different websites take different anti-crawl measures, which may be restricted based on factors such as access behavior, source IP, and so on. Some websites may use captCHA, human-machine verification and other means to identify machine access, resulting in proxy IP can not get the data properly.
To sum up, there are many reasons why proxy IP cannot access public data when crawling data, including the anonymity of proxy IP, request frequency, request rule, IP request times and other factors. In order to avoid these problems, crawler engineers need to consider these factors when designing the crawler strategy, select the appropriate proxy IP, reasonably control the request frequency, and increase randomness, so as to ensure the stable operation of crawler and smooth acquisition of required data.