mysql 启动报错:read-only file system

MySQL启动时报"read-only file system"错误通常是由于操作系统将MySQL的数据文件所在的文件系统设置为了只读模式。这可能是出于安全原因，比如备份策略或者防止意外修改数据。当尝试在一个只读文件系统上创建、删除或更改数据库文件时，MySQL会遇到这个问题。

解决这种问题通常有以下几个步骤：

1. **临时改变权限**：你可以通过命令行切换到root用户并挂载只读文件系统为可写，但这不是长期解决方案，因为重启后可能会再次变回只读。

   sudo mount -o remount,rw /mount_point/

2. **修改配置**：如果可能，检查my.cnf配置文件，确认data目录是否设置为只读，如果是的话，去掉只读标志。

   [mysqld]
   datadir=/path/to/data

3. **移除只读属性**：如果数据目录本身就是只读，需要解除其只读状态，然后移动或复制数据到一个新的非只读位置。

4. **恢复或重建数据**：如果无法临时修改，可能需要从备份恢复数据，或者在新的磁盘上安装MySQL，并迁移数据。

5. **联系管理员**：如果是服务器级别的问题，最好联系系统的管理员来处理这个设置，因为他们可能有特定的理由让文件系统保持只读。

相关问题

mysql Variable 'secure_file priv' is a read only variable

MySQL's "secure_file_priv" system variable determines the directory location where the LOAD DATA INFILE and SELECT INTO OUTFILE statements can read and write files. By default, this variable is set to the empty string (''), which means that these statements can access any file on the server.

If you are getting the "Variable 'secure_file_priv' is a read-only variable" error, it means that you are trying to change the value of this variable, which is not allowed. This error typically occurs when you try to set the "secure_file_priv" variable using the SET command or by modifying the my.cnf configuration file.

To solve this problem, you need to modify the "secure_file_priv" variable in the MySQL configuration file (my.cnf) and restart the MySQL server. Here are the steps:

1. Open the my.cnf configuration file in a text editor.

2. Locate the line that sets the "secure_file_priv" variable. If the line is commented out (with a # at the beginning), remove the # to uncomment it.

3. Set the "secure_file_priv" variable to the directory location where you want to allow access to files. For example, you can set it to "/var/lib/mysql-files".

4. Save the my.cnf configuration file.

5. Restart the MySQL server for the changes to take effect.

After following these steps, you should be able to use the LOAD DATA INFILE and SELECT INTO OUTFILE statements without getting the "Variable 'secure_file_priv' is a read-only variable" error.

Starting MySQL . ERROR! The server quit without updating PID file (/usr/local/mysql/data/macdeMacBook-Pro.local.pid).

It seems that you are facing an issue while starting MySQL. The error message suggests that the server quit without updating the PID file. This can happen due to various reasons, such as improper shutdown of the server or permission issues with the PID file.

To resolve this issue, you can try the following steps:

1. Check the permissions of the PID file: Ensure that the user running MySQL has the necessary permissions to read and write to the PID file. You can use the `ls -l` command to check the permissions and make any necessary changes using the `chmod` command.

2. Remove the existing PID file: If the PID file exists but is not being updated, you can try removing it. Run the following command to remove the PID file:

   sudo rm /usr/local/mysql/data/macdeMacBook-Pro.local.pid

3. Start MySQL again: After removing the PID file, try starting MySQL again. Depending on your setup, you can use commands like `sudo service mysql start` or `/usr/local/mysql/bin/mysqld_safe` to start the server.

If the issue persists, it might be helpful to check the MySQL error logs for more information about the error. The logs are usually located in the MySQL data directory or specified in the MySQL configuration file (my.cnf).

Please note that the steps provided here are general troubleshooting steps, and they may vary based on your specific setup and operating system.