The reasons why crawlers need a large number of IPs: 1. Because in the process of crawling data, the crawler is often prohibited from access by the website; 2. The crawled data is different from the data normally displayed on the page, or It says that the crawled data is blank data.
Why do you need a large number of IP addresses to do a crawler? Because in the process of crawling data, the crawler is often blocked from access by the website,
There is also a problem that the data you crawled is different from the data normally displayed on the page, or that you crawled blank data. It is likely that there is a problem with the program that creates the page on the website; if the crawling frequency is too high, If the website sets a threshold, access will be prohibited. Therefore, crawler developers generally use two methods to deal with this problem:
One is to slow down the crawling speed to reduce the pressure on the target website. . However, this will reduce the amount of crawling per unit time.
The second type of method is to use methods such as setting proxy IPs to break through the anti-crawler mechanism and continue high-frequency crawling, but this requires many stable proxy IPs. Sesame HTTP proxy IP can be used by crawler workers with confidence.
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