How to solve 502 error?

Why does the 502 Bad Gateway page pop up when opening a web page? In order to solve this problem, let’s first understand what a 502 Bad Gateway is.

502 Bad Gateway is a manifestation of a communication error with the website server. 502 is an error type code. It cannot indicate what is wrong with the website. When the server encounters a problem and the customer browses the web page, the web page will display 502 Bad Gateway.

So how to solve this problem? We will introduce five common solutions that can resolve most 502 Bad Gateway failures.

1. Check the server connection

Most websites are run through multiple servers or third-party proxies. If the server you are on is shut down due to maintenance or other reasons, a 502 Bad Gateway Error page may appear on your website. The only solution is to wait for the server to complete maintenance or fix the fault.

2. Check whether the DNS has been changed

If you have recently changed the host server or moved the website to another IP address, the DNS server of the website will be changed. This may cause the website to be inaccessible and a 502 Bad Gateway Error page appears. Before these DNS changes are completed, it may take a few minutes for your website to be up and running.

3. Check the server log

The task of the server's diary is to record the entire process of the website being visited, who has been there at what time, and what time. The search engine has come to see if your webpage has been indexed. You can use it to check the health status of your website. Careful inspection of the log contents may reveal the problem.

4. Repair firewall failure

The website firewall is equivalent to the guardian of the website, protecting your website from the intrusion of illegal users and distributed denial of service (DDOS) s attack. Sometimes, incorrect firewall settings cause the firewall to treat access requests coming from the content delivery network (CDN) as an attack on the server and therefore deny access, resulting in a 502 Bad Gateway.

5. Comb through the website code to find vulnerabilities

If there is an error in the website code, the server may not be able to respond to requests from the Content Delivery Network (CDN). Comb through code to find vulnerabilities or copy code into development tools. It will perform a thorough program debugging process that will simulate how a 502 Bad Gateway occurs to identify vulnerabilities.

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