+ +

Logging Sample Configuration File

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.

Note that the contents below are not intended to be copied and used as the basis for +a real homeserver.yaml. Instead, if you are starting from scratch, please generate +a fresh config using Synapse by following the instructions in +Installation.

# Log configuration for Synapse.
+#
+# This is a YAML file containing a standard Python logging configuration
+# dictionary. See [1] for details on the valid settings.
+#
+# Synapse also supports structured logging for machine readable logs which can
+# be ingested by ELK stacks. See [2] for details.
+#
+# [1]: https://docs.python.org/3.7/library/logging.config.html#configuration-dictionary-schema
+# [2]: https://github.com/matrix-org/synapse/blob/master/docs/structured_logging.md
+
+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. This means that
+    # will be a delay for INFO/DEBUG logs to get written, but WARNING/ERROR
+    # logs will still be flushed immediately.
+    buffer:
+        class: logging.handlers.MemoryHandler
+        target: file
+        # The capacity is the 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.
+        capacity: 10
+        flushLevel: 30  # Flush for WARNING logs as well
+
+    # 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
+``__`

+ +