Log4r is not writing logs after few days( 7 days)

Question

Two instance of process were running on each server(total 2 servers) and it stopped writing logs in all 4 logs file(each process has its respective log file) after a week when process were started. Process are still running but each process has stopped updating its respective log files.

Below is how i initialized log4r and and writing log.

@@logger = Log4r::Logger.new(@@log_name)
@@logger.outputters = Log4r::RollingFileOutputter.new(@@log_name,
                            :filename => log_filename,
                            :maxsize => max_log_size,
                            :maxtime => max_log_time,
                            :trunk => true,
                            :max_backups => max_backup_logs)
@@logger.debug "logs string"

here max size was 104MB, Time was 604800 sec and max backups set to 0.