Logging
Stellar Core sends logs to standard error and stellar-core.log by default, configurable with the LOG_FILE_PATH field.
Log messages are classified by progressive priority levels: TRACE, VERBOSE, DEBUG, INFO, WARNING, ERROR, and FATAL. The logging system only emits those messages at or above its configured logging level.
Log messages at different priority levels can be color-coded on standard error by setting LOG_COLOR=true in the config file. By default they are not color-coded.
The log level can be controlled by configuration, the -ll command-line flag, or adjusted dynamically by administrative (HTTP) commands. To do so, run:
$ stellar-core http-command "ll?level=debug"
while your node is running.
Log levels can also be adjusted on a partition-by-partition basis through the administrative interface. For example the history system can be set to DEBUG-level logging by running:
stellar-core http-command "ll?level=debug&partition=history"
Against a running system.
Please take a look at the HTTP Commands reference for more information about the partitions available for use in the ll command.
The default log level is INFO, which is moderately verbose and should emit progress messages every few seconds under normal operation.