Below is a sample logging configuration file. This file can be tweaked to control how your
homeserver will output logs. A restart of the server is generally required to apply any
changes made to this file. The value of the
log_config option in your homeserver
config should be the path to this file.
Note that a default logging configuration (shown below) is created automatically alongside
the homeserver config when following the installation instructions.
It should be named
<SERVERNAME>.log.config by default.
# Log configuration for Synapse. # # This is a YAML file containing a standard Python logging configuration # dictionary. See  for details on the valid settings. # # Synapse also supports structured logging for machine readable logs which can # be ingested by ELK stacks. See  for details. # # : https://docs.python.org/3.7/library/logging.config.html#configuration-dictionary-schema # : https://matrix-org.github.io/synapse/latest/structured_logging.html version: 1 formatters: precise: format: '%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s - %(message)s' handlers: file: class: logging.handlers.TimedRotatingFileHandler formatter: precise filename: /var/log/matrix-synapse/homeserver.log when: midnight backupCount: 3 # Does not include the current log file. encoding: utf8 # Default to buffering writes to log file for efficiency. # WARNING/ERROR logs will still be flushed immediately, but there will be a # delay (of up to `period` seconds, or until the buffer is full with # `capacity` messages) before INFO/DEBUG logs get written. buffer: class: synapse.logging.handlers.PeriodicallyFlushingMemoryHandler target: file # The capacity is the maximum number of log lines that are buffered # before being written to disk. Increasing this will lead to better # performance, at the expensive of it taking longer for log lines to # be written to disk. # This parameter is required. capacity: 10 # Logs with a level at or above the flush level will cause the buffer to # be flushed immediately. # Default value: 40 (ERROR) # Other values: 50 (CRITICAL), 30 (WARNING), 20 (INFO), 10 (DEBUG) flushLevel: 30 # Flush immediately for WARNING logs and higher # The period of time, in seconds, between forced flushes. # Messages will not be delayed for longer than this time. # Default value: 5 seconds period: 5 # A handler that writes logs to stderr. Unused by default, but can be used # instead of "buffer" and "file" in the logger handlers. console: class: logging.StreamHandler formatter: precise loggers: synapse.storage.SQL: # beware: increasing this to DEBUG will make synapse log sensitive # information such as access tokens. level: INFO twisted: # We send the twisted logging directly to the file handler, # to work around https://github.com/matrix-org/synapse/issues/3471 # when using "buffer" logger. Use "console" to log to stderr instead. handlers: [file] propagate: false root: level: INFO # Write logs to the `buffer` handler, which will buffer them together in memory, # then write them to a file. # # Replace "buffer" with "console" to log to stderr instead. (Note that you'll # also need to update the configuration for the `twisted` logger above, in # this case.) # handlers: [buffer] disable_existing_loggers: false