anchor.diff:  --
   [source,yaml]
   ----
  -logger.org.elasticsearch.transport: TRACE
  +logger.org.elasticsearch.discovery: DEBUG
   ----
   
   This is most appropriate when debugging a problem on a single node.
  
positive.code: === Configuring logging levels
  
  Each Java package in the {es-repo}[{es} source code] has a related logger. For
  example, the `org.elasticsearch.transport` package has
  `logger.org.elasticsearch.transport` for logs related to communication between
  nodes.
  
  To get more or less verbose logs, use the <<cluster-update-settings,cluster
  update settings API>> to change the related logger's log level. Each logger
  accepts Log4j 2's built-in log levels, from least to most verbose: `OFF`,
  `FATAL`, `ERROR`, `WARN`, `INFO`, `TRACE`, and `DEBUG`. The default log level is
  `INFO`.
  
  [source,console]
  ----
  PUT /_cluster/settings
  {
    "transient": {
      "logger.org.elasticsearch.transport": "TRACE"
    }
  }
  ----
  
negative.code: --
  [source,properties]
  ----
  logger.org.elasticsearch.discovery.level = debug
  ----
  
  This is most appropriate when you already need to change your Log4j 2
  