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25.3.5. Log Rotation

The following is a sample /etc/logrotate.conf configuration file:
# rotate log files weekly
# keep 4 weeks worth of backlogs
rotate 4
# uncomment this if you want your log files compressed
All of the lines in the sample configuration file define global options that apply to every log file. In our example, log files are rotated weekly, rotated log files are kept for four weeks, and all rotated log files are compressed by gzip into the .gz format. Any lines that begin with a hash sign (#) are comments and are not processed.
You may define configuration options for a specific log file and place it under the global options. However, it is advisable to create a separate configuration file for any specific log file in the /etc/logrotate.d/ directory and define any configuration options there.
The following is an example of a configuration file placed in the /etc/logrotate.d/ directory:
/var/log/messages {
    rotate 5
    /usr/bin/killall -HUP syslogd
The configuration options in this file are specific for the /var/log/messages log file only. The settings specified here override the global settings where possible. Thus the rotated /var/log/messages log file will be kept for five weeks instead of four weeks as was defined in the global options.
The following is a list of some of the directives you can specify in your logrotate configuration file:
  • weekly — Specifies the rotation of log files to be done weekly. Similar directives include:
    • daily
    • monthly
    • yearly
  • compress — Enables compression of rotated log files. Similar directives include:
    • nocompress
    • compresscmd — Specifies the command to be used for compressing.
    • uncompresscmd
    • compressext — Specifies what extension is to be used for compressing.
    • compressoptions — Specifies any options to be passed to the compression program used.
    • delaycompress — Postpones the compression of log files to the next rotation of log files.
  • rotate INTEGER — Specifies the number of rotations a log file undergoes before it is removed or mailed to a specific address. If the value 0 is specified, old log files are removed instead of rotated.
  • mail ADDRESS — This option enables mailing of log files that have been rotated as many times as is defined by the rotate directive to the specified address. Similar directives include:
    • nomail
    • mailfirst — Specifies that the just-rotated log files are to be mailed, instead of the about-to-expire log files.
    • maillast — Specifies that the about-to-expire log files are to be mailed, instead of the just-rotated log files. This is the default option when mail is enabled.
For the full list of directives and various configuration options, see the logrotate(5) manual page.