config/environments/production.rb

@@ -125,6 +125,9 @@ Rails.application.configure do
   # Send deprecation notices to registered listeners.
   config.active_support.deprecation = :notify
 
+  # Specify the log level
+  config.log_level = ENV["RAILS_LOG_LEVEL"].present? ? ENV['RAILS_LOG_LEVEL'].to_sym : :info
+
   # Use Lograge for logging
   config.lograge.enabled = true
 
@@ -141,8 +144,6 @@ Rails.application.configure do
     "#{time} - #{severity}: #{msg} \n"
   end
 
-  config.log_level = :info
-
   # Prepend all log lines with the following tags.
   config.log_tags = [:request_id, :remote_ip]
 

sample.env

@@ -259,6 +259,11 @@ ENABLE_SSL=true
 # RAILS_LOG_REMOTE_PORT=9999
 # RAILS_LOG_REMOTE_TAG=greenlight
 
+# Specify the log level
+# Allowed values are: debug|info|warn|error|fatal|unknown
+# For details, see: https://docs.ruby-lang.org/en/master/Logger.html
+#RAILS_LOG_LEVEL=info
+
 # Database settings
 #
 # Greenlight may work out of the box with sqlite3, but for production it is recommended to use postgresql.