We have encountered a very difficult case of Baidu indexation. The process of analyzing and solving this issue was tricky and entertaining.

The cause of the Baidu indexation was the revision of our foreign customer’s website in mid-September 2022. After the revision was launched, the customer found that the website was frequently attacked, and therefore the customer IT enabled the function of preventing Internet attacks (Bot Management) in its Cloudflare content distribution system (CDN). After that, Baidu SEO performed abnormally.

• In October 2022, we found that Baidu crawling was blocked through Baidu webmaster.
• From November 2022 to February 2023, the number of Baidu indexes continued to decline, and the keyword ranking disappeared gradually.
• In February 2023, the website shut down Bot Management. Baidu crawling returned to normal, and the homepage of the website was also included again.
• In February 2023, the bot attack occurred again on the website, and Bot Management had to be re-enabled. We observed that there was a record of blocking Baidu crawling in Baidu webmaster.
• In February 2023, IT made customized settings of Bot Management in Cloudflare.
• In March 2023, we observed that there were still records of blocking Baidu crawling in Baidu webmaster.
• In March 2023, IT continued to modify the configuration of Bot Management, but there were still records of Baidu crawling being blocked.
• In April 2023, after repeatedly modifying the configuration of Bot Management, we did not find any records of Baidu crawling being blocked in Baidu webmaster. Even so, Baidu indexation and keywords ranking remained the same without major changes.

At this point, the SEO of the website seemed to be in trouble. We have done everything that should be done, but the website indexation didn’t go back to normal.

What should we do?

At this time, we asked IT to provide logfiles of the website. We hope to find out what causes the abnormal indexation and SEO rankings through viewing and analyzing the logs.

In the blocking records of Cloudflare’s Bot Management, we found that there were many IPs in the range of 220.181.108.*, and these IPs are the IP addresses of Baidu’s servers in various parts of China. We then recommended the customer to allow these IPs requests in Bot Management.

In May 2023, the number of website indexation began to pick up, and the keyword rankings gradually returned to normal.

From this case, we draw the following two important conclusions:

1. Everything is normal in Baidu Webmaster does not mean that everything is fine.
2. The SEO issues may be caused by many factors. Some are easy to judge, and some are very obscure and difficult to detect. In some cases, we need to dig into logfiles to find out the real reason that affects SEO and the right solution on that.