Automatic Log Rotation in Rails

Rails log files rotate automatically when they reach approx. 100MB:

Copy$ ls -lh log/
-rw-r--r-- 1 user group  55M Sep 15 09:54 development.log
-rw-r--r-- 1 user group 101M Aug 22 13:45 development.log.0

This behavior is a built-in feature Show archive.org snapshot of Ruby's standard Logger class, which Rails uses by default.

To control the maximum file size, set config.log_file_size in your environment configuration. This is useful for keeping log files manageable, especially in development and test environments.

Copy# config/environments/development.rb

Rails.application.configure do
  config.log_file_size = 10.megabytes
end

When this value is set, Rails initializes the logger to rotate the log file and keep one old version, which is overwritten on the next rotation. In production, you could use periodic rotation Show archive.org snapshot to rotate log files every day for a week or something similar.