查看logger信息，更新logger level ### 使用参考 #### 查看所有logger信息 `logger`{{execute T2}} ```bash [arthas@2062]$ logger name ROOT class ch.qos.logback.classic.Logger classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 level INFO effectiveLevel INFO additivity true codeSource file:/Users/hengyunabc/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar appenders name CONSOLE class ch.qos.logback.core.ConsoleAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 target System.out name APPLICATION class ch.qos.logback.core.rolling.RollingFileAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 file app.log name ASYNC class ch.qos.logback.classic.AsyncAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 appenderRef [APPLICATION] ``` #### 查看指定名字的logger信息 `logger -n org.springframework.web`{{execute T2}} ```bash [arthas@2062]$ logger -n org.springframework.web name org.springframework.web class ch.qos.logback.classic.Logger classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 level null effectiveLevel INFO additivity true codeSource file:/Users/hengyunabc/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar ``` 请记下你的classLoaderHash，后面需要使用它。在这里，它是 `2a139a55`。 注意：请使用你的classLoaderHash值覆盖 `` ，然后手动执行下面所述命令： #### 查看指定classloader的logger信息 `logger -c ` ```bash [arthas@2062]$ logger -c 2a139a55 name ROOT class ch.qos.logback.classic.Logger classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 level DEBUG effectiveLevel DEBUG additivity true codeSource file:/Users/hengyunabc/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar appenders name CONSOLE class ch.qos.logback.core.ConsoleAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 target System.out name APPLICATION class ch.qos.logback.core.rolling.RollingFileAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 file app.log name ASYNC class ch.qos.logback.classic.AsyncAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 appenderRef [APPLICATION] ``` #### 更新logger level `logger --name ROOT --level debug`{{execute T2}} ```bash [arthas@2062]$ logger --name ROOT --level debug update logger level success. ``` #### 指定classloader更新 logger level 默认情况下，logger命令会在SystemClassloader下执行，如果应用是传统的`war`应用，或者spring boot fat jar启动的应用，那么需要指定classloader。 可以先用 `sc -d yourClassName` 来查看具体的 classloader hashcode，然后在更新level时指定classloader： `logger -c --name ROOT --level debug` ```bash [arthas@2062]$ logger -c 2a139a55 --name ROOT --level debug ``` #### 查看没有appender的logger的信息 默认情况下，`logger`命令只打印有appender的logger的信息。如果想查看没有`appender`的logger的信息，可以加上参数`--include-no-appender`。 注意，通常输出结果会很长。 `logger --include-no-appender`{{execute T2}} ```bash [arthas@2062]$ logger --include-no-appender name ROOT class ch.qos.logback.classic.Logger classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 level DEBUG effectiveLevel DEBUG additivity true codeSource file:/Users/hengyunabc/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar appenders name CONSOLE class ch.qos.logback.core.ConsoleAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 target System.out name APPLICATION class ch.qos.logback.core.rolling.RollingFileAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 file app.log name ASYNC class ch.qos.logback.classic.AsyncAppender classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 appenderRef [APPLICATION] name com class ch.qos.logback.classic.Logger classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 level null effectiveLevel DEBUG additivity true codeSource file:/Users/hengyunabc/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar name com.alibaba class ch.qos.logback.classic.Logger classLoader sun.misc.Launcher$AppClassLoader@2a139a55 classLoaderHash 2a139a55 level null effectiveLevel DEBUG additivity true codeSource file:/Users/hengyunabc/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar ... ```