Log files are useful when you want to know what is going on in your system. Logrotate is a perfect tool to manage your log files. If it is not already installed, you can install it by:

sudo apt-get install logrotate

Then you can edit the config file and add the log file that you want it to manage.

sudo pico /etc/logrotate.conf

A sample configuration to rotate your Rails production log:

/home/ubuntu/app_name/log/production.log {
    daily
    missingok
    rotate 15
    delaycompress
    notifempty
    copytruncate
}

You can define the filenames by wildcard such as:

/log/*_production.log {
}

Common configuration includes:

• rotate - How many files you want to keep?
• daily/weekly/monthly/yearly - How often a file rotate?
• compress/nocompress/delaycompress - Whether or not the old log is compressed?
• size - if you want to rotate by size
• copytruncate - when a rotate happens, clear the content of original log file by moving it to another file
• notifempty - Do not rotate the log if it is empty.
• missingok - Doesn't matter if the log file is missing.

Full list can be found here.