Control over biserver.out file using Weblogic console

We may face  where the biserver.out/log  file size grows dynamically and causes disk space issues/limit on production environments to overcome you have to set few parameters on weblogic console below changes will reflect both bi_server.out and bi_server.log files

Go to the Weblogic console -> Servers -> biserver --> Logging -> General Tab

To move old messages to another file when the current log file reaches a specific size:

1. In the Rotation Type list box, choose By Size.
   
2. In the Rotation File Size field, enter the file size that triggers the server to move log messages to a separate file. After the log file reaches the specified size, the next time the server checks the file size it renames the current log file by appending a 5-digit integer; for example, SERVER_NAME.log00007. After the server renames the file, subsequent messages accumulate in a new file named SERVER_NAME.log.
   
3. If you want to limit the number of log files that the server creates to store old log messages, select the Limit Number of Retained Files check box. Then in the Files to Retain field, enter the maximum number of files. If the server receives additional log messages after reaching the capacity of the last log file, it overwrites the oldest log file.
   

 If you want to move old messages to another file at specific time intervals:

1. In the Rotation Type list box, choose By Time.In the Begin Rotation Time field, enter the start time.
   
2. Use the following format: hh:mm, where hh is the hour in a 24-hour format and mm is the minute. At the time that you specify, the server rotates the current log file. If the time that you specify is already past, the server rotates the log file at the next scheduled interval, as specified in Rotation Interval.
   
3. In the Rotation Interval field, enter the interval at which the server saves old messages to another file.If you want to limit the number of log files that the server creates to store old log messages, select the Limit Number of Retained Log Files check box. Then in the Files to Retain field, enter the maximum number of files. If the server receives additional log messages after reaching the capacity of the last log file, it overwrites the oldest log file.
   

Reference : http://docs.oracle.com/cd/E23943_01/apirefs.1111/e13952/taskhelp/logging/RotateLogFiles.html