1. Login to Plesk Panel.
2. Click on "Domains" under "Hosting Services".
3. Select the domain for which you need to set/edit log rotation.
4. Click on "Websites & Domains" tab.
5. Click on " Show Advanced Operations ".
6. Click on "Logs".
7. Select "Log Rotation" and Click "Switch On" in the Tools group.
If you see only Switch Off there, this means that log recycling is already switched on.
Specify when to recycle log files and how many instances of each log file to store on the server.
Also specify whether they should be compressed or not and sent to an e-mail address after processing.
Note : Please note that there are two option for "Log rotation condition".
1. by size (in KiloBytes)
2. by time (Daily,Weekly,Monthly)
8. Click on "OK" once you have made the required settings.