From Fedora Project Wiki

Fedora Log Files

This document describes the guidelines for log file(s), for use and inclusion in Fedora packages.

For the purposes of these guidelines, a log file is defined as an text file that an application outputs into in the /var/log/ directory.

Log Files on the filesystem

Packages with log files must reside in their own directory under /var/log which must be named /var/log/$package_name

Each log file in that directory must end with .log filename.

Each package that ships log file(s) must also ship a logrotation file that rotates the log file(s).

Log Files Packaging

...

Name:
.....
Source1: %{name}.logrotate
Requires: logrotate

%install
...
mkdir -p $RPM_BUILD_ROOT%{_localstatedir}/log/%{name}
mkdir -p $RPM_BUILD_ROOT%{_sysconfdir}/logrotate.d
%{__install} -p -D -m 0700 %{SOURCE1} $RPM_BUILD_ROOT%{_sysconfdir}/logrotate.d/%{name}.conf

%files
...
%config(noreplace) %{_sysconfdir}/logrotate.d/%{name}.conf
%dir %attr(0700,root,root) %{_localstatedir}/log/%{name}

Logrotate file

If a package contains a logfile then it needs to also include a properly installed logrotate file.

Each logrotate file must end with the filename .conf. It must be placed /etc/logrotate.d/ and must have 0644 filepermission and be owned by root.

Here are examples of an logrotate file.

Example minimal logrotate file

/var/log/example/*log {
	missingok		# If the log file is missing, go on to the next one without issuing an error message
	notifempty		# Don't do any rotation if the logfile is empty
	compress		# Compress older files with gzip
	delaycompress		# Don't compress yesterdays files
}

Example minimal logrotate log file with user create mode

/var/log/example/*log {
	missingok		# If the log file is missing, go on to the next one without issuing an error message
	notifempty		# Don't do any rotation if the logfile is empty
	compress		# Compress older files with gzip
  	delaycompress		# Don't compress yesterdays files
	create 640 owner group  # Set create mode immediately after rotation
}

Example minimal logrotate file with daemon restart

/var/log/example/*log {
	missingok		# If the log file is missing, go on to the next one without issuing an error message
	notifempty		# Don't do any rotation if the logfile is empty
	compress		# Compress older files with gzip
  	delaycompress		# Don't compress yesterdays files
	sharedscripts		# Scripts are only run once for all files in directory
	postrotate
		/usr/bin/systemctl restart example.service 2>/dev/null || true
	endscript
}

Example minimal logrotate file with user create mode and daemon restart

/var/log/example/*log {
	missingok		# If the log file is missing, go on to the next one without issuing an error message
	notifempty		# Don't do any rotation if the logfile is empty
	compress		# Compress older files with gzip
  	delaycompress		# Don't compress yesterdays files
	create 640 owner group  # Set create mode immediately after rotation
	sharedscripts		# Scripts are only run once for all files in directory
	postrotate
		/usr/bin/systemctl restart example.service 2>/dev/null || true
	endscript
}
Debugging logrotate file
You can debug your logrotate file by running
# logrotate -d -f /etc/logrotate.d/example.conf
from the command line.