Common causes and solutions for php 404 errors

In the process of using PHP to develop websites, 404 file or directory not found errors often occur. This error is usually caused by the file or directory not existing or the permissions of the file or directory being incorrect. This article will detail the common causes, solutions, and preventive measures for PHP 404 errors.

1. Common reasons

1. The file or directory does not exist

When we access a URL that does not exist, a 404 error will occur. At this time, you need to check whether the requested file or directory exists. If it does not exist, you need to modify the code or re-upload the file or directory.

2. The permissions of the file or directory are incorrect

If the permissions of the file or directory are incorrect, it will also cause a 404 error. This is usually caused by an incorrect owner or group of the file or directory. You can modify the permissions of files or directories through the chmod command.

3. Routing configuration errors

When using the PHP framework, routing configuration errors can also cause 404 errors. It is necessary to check whether the routing configuration file is correct and ensure that the requested route and controller methods exist.

4. Pseudo-static setting error

When using pseudo-static, if the rule setting is incorrect, it will also cause a 404 error. You need to check whether the pseudo-static rules are set correctly.

2. Processing method

1. Check whether the file or directory exists

When a 404 error occurs, you need to first check whether the file or directory exists. . You can access the server through FTP or SSH and check whether the file or directory exists in the requested path. If it exists, you can try to upload the file or directory again. If it does not exist, you need to modify the code or recreate the file or directory.

2. Modify the permissions of the file or directory

If the permissions of the file or directory are incorrect, you can modify the permissions through the chmod command. Generally speaking, it can be set to 755 or 777 permissions. It is important to note that do not set the directory as owner or group as Apache, otherwise it will lead to security vulnerabilities.

3. Change the routing configuration file

When there is a problem with the routing configuration file, you can check the specific error information from the console or log. Modify the routing configuration file according to the error message to ensure the correctness of routing and controller methods.

4. Check the pseudo-static rule settings

When using pseudo-static, you need to check whether the pseudo-static rule settings are correct. You can refer to the documentation of Apache or Nginx for settings.

3. Preventive measures

1. Restrict the access rights to the directory

In order to ensure the security of the website, it is recommended to limit the access rights to the directory Restrict to only allow Apache or Nginx access. You can set the user group to which the directory belongs on the server to Apache or Nginx.

2. Regularly back up website data

Regularly backing up website data can quickly restore website data when problems occur and avoid website data loss.

3. Use security protection measures

In order to prevent the website from being attacked by hackers, you need to use security protection measures, such as installing a firewall, setting up website access logs, etc.

In short, when using PHP to develop a website, you need to pay attention to the permission settings of files or directories, routing configuration and pseudo-static rule settings to avoid 404 errors. At the same time, it is also necessary to strengthen the security protection of the website and perform data backup to ensure the normal operation of the website.

The above is the detailed content of Common causes and solutions for php 404 errors. For more information, please follow other related articles on the PHP Chinese website!