Logs

Logs provide a reliable source of information for troubleshooting and system performance optimization. You can find the record about the access, operating, or network issues from EMQX logs.

EMQX log has 8 levels, with warning as the default level, from low to high these 8 levels are:

debug < info < notice < warning < error < critical < alert < emergency

You can configure EMQX logs with Dashboard or configuration files. To configure with EMQX Dashboard, you can click Management -> Log on the left navigation menu to configure.

TIP

Most configuration items listed here also can be configured with Dashboard, and their Dashboard UI fields are also introduced on this page. Once you configured these items with the Dashboard, your settings will override the same configuration items in emqx.conf.

This section introduces how to configure logs with configuration items. For example, if you want to export the logs of warning levels as both a file and output with a console, you can work with the following configuration items.

log {
  file_handlers.default {
    level = warning
    file = "log/emqx.log"
    count = 10
    max_size = 50MB
    formatter = text
  }
  console_handler {
    level = warning
    formatter = text
  }
}

Output Logs as a File

To output logs as a file, you can work with the command below:

Code example:

log {
  file_handlers.default {
    level = warning
    file = "log/emqx.log"
    count = 10
    max_size = 50MB
    formatter = text
  }

Where,

Output log with Console

You can also use the command below to configure the logs with the console:

log {
  console_handler {
    level = warning
    formatter = text
  }
}

Where,

TIP

To configure listeners via Dashboard, click Configuration -> Log on the left navigation menu of the Dashboard. Once you configured these items with the Dashboard, your settings will override the same configuration items in emqx.conf.

EMQX has offered more configuration items to better serve customized needs, you can continue to read Configuration Manual.