This issue was raised by Kireet on the log4j-user mailing list:
I am trying to use the rolling file appender in log4j2, basically I want to roll at midnight daily and keep 3 old log files. New files are created properly, but log4j doesn't seem to be cleaning up the old files. Does log4j only support cleanup of files within the time period? Here is the relevant portion of the config. I tried things with and without the %i pattern.