Merge pull request #3256 from zmstone/251121-fix-log-levels

docs: fix log levels

Author: zmstone

en_US/observability/log.md

@@ -15,23 +15,21 @@ To minimize the impact of logs on system operation, for example, when the log da
 
 ## Log Level
 
-EMQX log has 8 levels ([RFC 5424](https://www.ietf.org/rfc/rfc5424.txt)), with warning as the default level, from low to high these 8 levels are:
+EMQX log has 6 out of the 8 levels ([RFC 5424](https://www.ietf.org/rfc/rfc5424.txt)), with warning as the default level, from low to high these levels are:
 
 ```bash
-debug < info < notice < warning < error < critical < alert < emergency
+debug < info < notice < warning < error < critical
 ```
 The table below describes the meaning and output contents for each log level.
 
 | Log Level | Meaning                                                      | Output Examples                                              |
 | --------- | ------------------------------------------------------------ | ------------------------------------------------------------ |
 | debug     | Detailed information about the internal workings of a program, helping to debug and diagnose issues in the code. <br />It is not recommended to output this level of logging directly to the production environment. Instead, enable [Log Trace](./tracer.md) for a specific client. | Variable values, function call stacks, and other detailed debugging data. |
-| info      | Useful information that is more general than debug-level logs. | Client connections, subscriptions, publishes, QoS levels, and message delivery status. |
-| notice    | Important system information indicating that an event has occurred, but no action is required. | Number of clients connected to the proxy server, number of reconnections attempted, and number of crashed nodes. |
+| info      | Useful information that is more general than debug-level logs. | Minor abnormalities such as authorization denial, and management operation results, such as a successful configuration change. |
+| notice    | Important system information indicating that an event has occurred, but no action is required. | Component restarted per request from dashboard or CLI |
 | warning   | Potential issues or errors that require action; typically used for proactive monitoring and detecting potential problems before they become critical issues. | Disconnections, connection timeouts, authentication failures, and other similar events. |
 | error     | The occurrence of an error that requires error handling; typically used to flag errors so that administrators can quickly detect and resolve issues. | Fails to connect to an external database, to subscribe to a non-existent topic, or to parse a configuration file, or other similar events. |
-| critical  | Critical error that results in system crashes or prevents it from functioning; typically used to flag severe problems so that administrators can take immediate action. | Proxy server crashes, database unavailability, and other similar events. |
-| alert     | Severe problems that may cause the application to stop and need to take immediate action to prevent further losses. | The application has reached a critical threshold, such as running out of disk space or memory, or a critical system process has crashed or stopped responding. |
-| emergency | Extremely serious problems that prevent the application from running and require immediate action; happen in rare circumstances. | Failure in data synchronizing between different nodes.       |
+| critical  | Critical error that results in system crashes or prevents it from functioning; typically used to flag severe problems so that administrators can take immediate action. | A component is unable to start or function normally due to incorrect configuration. |
 
 ## Configure Logging via Dashboard
 
@@ -79,7 +77,7 @@ Configure the following settings for file log handler:
 
 - **Rotation Size**: Log file will be rotated once it reaches the specified size. It is by default enabled. You can type the specific value in the text box below. If you disable it, the value will be `infinity`, which means the log file will grow indefinitely.
 
-- **Log Level**: Select the log level to use from the drop-down list. Optional values are: `debug`, `info`, `notice`, `warning`, `error`, `critical`, `alert`, `emergency`. Default value is: `warning`.
+- **Log Level**: Select the log level to use from the drop-down list. Optional values are: `debug`, `info`, `notice`, `warning`, `error`, `critical`. Default value is: `warning`.
 
 - **Log Formatter**: Select the log format from the drop-down list. Optional values are `text` and `JSON`. The default value is `text`.
 

zh_CN/observability/log.md

@@ -15,24 +15,22 @@ EMQX 支持两种不同的日志输出方式：控制台输出日志和文件输
 
 ## 日志级别
 
-EMQX 日志包含 8 个等级 ([RFC 5424](https://www.ietf.org/rfc/rfc5424.txt))，默认为 warning 级别，由低到高分别为：
+EMQX 日志包含 8 个等级中的 6 个常用级别 ([RFC 5424](https://www.ietf.org/rfc/rfc5424.txt))，默认为 warning 级别，由低到高分别为：
 
 ```bash
-debug < info < notice < warning < error < critical < alert < emergency
+debug < info < notice < warning < error < critical
 ```
 
 下面的表格描述了每个日志级别的含义和输出内容。
 
 | 日志级别  | 含义                                                         | 输出内容                                                     |
 | --------- | ------------------------------------------------------------ | ------------------------------------------------------------ |
 | debug     | 调试级别的日志，包含最详细的信息和调试数据。仅在需要进行详细调试时才使用此级别的日志。不建议在生产环境直接输出该级别日志，可以使用 [日志追踪](./tracer.md) 为指定客户端开启。 | 通常包含最详细的调试信息、变量值、函数调用栈等信息。         |
-| info      | 提供有用的信息，比 debug 级别的日志更粗略                    | 如客户端连接、订阅、发布、QoS 等级别、消息传递等信息。       |
+| info      | 提供有用的信息，比 debug 级别的日志更粗略                    | 授权拒绝等轻微异常，以及管理操作的结果，例如成功的配置更改。 |
 | notice    | 提供重要的系统信息，表示有事件发生但不需要采取行动。         | 例如，连接到代理服务器的客户端数量、重连次数、崩溃的节点数量等。 |
 | warning   | 表示存在潜在的问题或错误，需要采取一定的行动； 此级别的日志通常用于发现问题和错误之前的预警。 | 连接断开、连接超时、认证失败等情况。                         |
 | error     | 表示出现了错误，需要进行错误处理；此级别的日志通常用于标记错误，以便管理员可以快速检测和解决问题 | 无法连接到外部数据库、订阅的主题不存在、未能解析配置文件等。 |
-| critical  | 表示出现了严重错误，导致系统崩溃或无法继续工作；此级别的日志通常用于标记严重问题，以便管理员可以尽快采取行动。 | 代理服务器崩溃、数据库无法访问等。                           |
-| alert     | 表示需要立即采取行动，以防止进一步的损失；此级别的日志记录将触发警报通知操作，并且可能导致应用程序的停止。 | 例如，应用程序已达到关键阈值，例如磁盘空间或内存耗尽，或关键系统进程已崩溃或停止响应。 |
-| emergency | 导致系统无法继续运行的严重错误；这种级别的日志通常只会在极少数情况下出现，并且需要立即对其进行处理。 | 例如，EMQX 节点间数据同步失败                                |
+| critical  | 表示出现了严重错误，导致系统崩溃或无法继续工作；此级别的日志通常用于标记严重问题，以便管理员可以尽快采取行动。 | 组件无法正常启动或运行，原因可能是配置不正确。               |
 
 ## 通过 Dashboard 修改日志配置
 
@@ -49,7 +47,7 @@ debug < info < notice < warning < error < critical < alert < emergency
 配置控制台日志处理进程的选项：
 
 - **启用日志处理进程**：单击切换开关以启用控制台日志处理进程。
-- **日志级别**：从下拉列表中选择要使用的日志级别。可选值为：`debug`, `info`, `notice`, `warning`, `error`, `critical`, `alert`, `emergency` 。默认值为：`warning`。
+- **日志级别**：从下拉列表中选择要使用的日志级别。可选值为：`debug`, `info`, `notice`, `warning`, `error`, `critical` 。默认值为：`warning`。
 - **日志格式类型**：从下拉列表中选择日志格式。可选值为：`text` 和 `json`。默认值为 `text`。
 - **时间戳格式**：从下拉列表中选择日志时间戳格式。可选值为：
   - `auto`: 根据所使用的日志格式类型自动确定时间戳格式。对于文本格式类型，使用 `rfc3339` 格式；对于 JSON 格式类型，则使用 `epoch`格式。
@@ -72,7 +70,7 @@ debug < info < notice < warning < error < critical < alert < emergency
 - **日志文件名字**：填写日志文件的名称。默认为`log/emqx.log`。
 - **最大日志文件数**：轮换的最大日志文件数。默认值为`10`。
 - **日志文件轮换大小**：设置日志文件大小，达到设定的值时日志文件将进行轮换。如果禁用，则日志文件将无限增长。可在文本框输入设定的值，在下拉列表中选择单位，可选值为：`MB`, `GB`, `KB`。
-- **日志级别**：从下拉列表中选择要使用的日志级别。可选值为：`debug`, `info`, `notice`, `warning`, `error`, `critical`, `alert`, `emergency` 。默认值为：`warning`。
+- **日志级别**：从下拉列表中选择要使用的日志级别。可选值为：`debug`, `info`, `notice`, `warning`, `error`, `critical` 。默认值为：`warning`。
 - **日志格式类型**：从下拉列表中选择日志格式。可选值为：`text` 和 `json`。默认值为 `text`。
 - **时间戳格式**：从下拉列表中选择日志时间戳格式。可选值为：
   - `auto`: 根据所使用的日志格式类型自动确定时间戳格式。对于文本格式类型，使用 `rfc3339` 格式；对于 JSON 格式类型，则使用 `epoch`格式。