Recently I ran into an issue with Paralles Plesk 11 for UNIX/Linux where log files for a specific virtual host took up a larger than normal amount of space. In Parallels Plesk 11 you can actually modifying log file settings through the Control Panel GUI.
The below are examples of some of the log files in Parallels Plesk 11 which grew large in size, approximately 200 MB each which chewed through hosting space.
Through GOOGLE I was able to fine the solution however it was not so easy to find. Below is s short guide to modify the Parallels Plesk 11 log files (may also be referred to log rotation)
Open Parallels Control Panel > Select Websites & Domains > Show Advanced Options > Select Logs > Under Tools select Log Rotation > Modify Log settings as required, click Ok or Cancel