Failed to start mysql.service: Unit mysql.service is masked.

这个错误通常意味着 `mysql.service` 被屏蔽了，因此无法启动。你可以解除屏蔽并重新启动 MySQL 服务，具体步骤如下：

1. 打开终端并以管理员身份运行以下命令：

   sudo systemctl unmask mysql.service

2. 然后启动 MySQL 服务：

   sudo systemctl start mysql.service

3. 最后，检查 MySQL 服务状态：

   sudo systemctl status mysql.service

如果 MySQL 服务已成功启动，则应该看到 "active (running)" 的状态。

相关问题

Failed to start firewalld.service: Unit is masked

这个问题与系统服务有关，特别是在Linux系统中。错误消息“Failed to start firewalld.service: Unit is masked”意味着firewalld服务无法启动，因为它被隐藏了。

Firewalld是一个防火墙守护程序，用于管理Linux系统上的网络防火墙规则。通常，它是由许多安全组和规则集组成的，用于控制网络流量。

错误消息“Failed to start firewalld.service: Unit is masked”通常意味着firewalld服务被系统管理员或root用户通过mask命令隐藏了。这可能是出于安全考虑，以防止firewalld在未授权的情况下启动。

要解决这个问题，你可以按照以下步骤操作：

1. 检查防火墙状态：首先，确保你的系统上已经安装了Firewalld服务。你可以使用以下命令检查防火墙状态：

systemctl status firewalld

如果防火墙未安装或未运行，你需要先安装并启动它。

2. 解除防火墙隐藏：如果你确定防火墙已经安装并运行，你可以使用以下命令解除防火墙的隐藏状态：

systemctl unmask firewalld

这将允许firewalld服务再次启动。

Failed to start docker.service: Unit is masked.

The error message "Failed to start docker.service: Unit is masked" typically indicates that the Docker service has been marked as masked, which means it is disabled and cannot be started. This can happen if there are issues with the Docker installation or if it has been intentionally masked by the system administrator.

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

1. Unmask the Docker service: Run the following command to unmask the Docker service.

   sudo systemctl unmask docker.service

2. Start the Docker service: Once the Docker service is unmasked, you can start it using the following command.

   sudo systemctl start docker.service

3. Verify the status: After starting the Docker service, you can check its status to ensure it is running without any errors.

   sudo systemctl status docker.service

If the issue persists or if you do not have administrative privileges to perform these actions, you may need to contact your system administrator for further assistance.