Ubuntu Manpage: logrotate ‐ rotates, compresses, and mails system logs

Provided by: logrotate_3.19.0-1ubuntu1.1_amd64

NAME

       logrotate ‐ rotates, compresses, and mails system logs

SYNOPSIS

       logrotate  [--force]  [--debug]  [--state  file]  [--skip-state-lock]  [--verbose]  [--log  file] [--mail
       command] config_file [config_file2 ...]

DESCRIPTION

       logrotate is designed to ease administration of systems that generate large numbers  of  log  files.   It
       allows  automatic rotation, compression, removal, and mailing of log files.  Each log file may be handled
       daily, weekly, monthly, or when it grows too large.

       Normally, logrotate is run as a daily cron job.  It will not modify a log  more  than  once  in  one  day
       unless  the  criterion  for that log is based on the log's size and logrotate is being run more than once
       each day, or unless the -f or --force option is used.

       Any number of config files may be given on the command line.  Later config files may override the options
       given  in  earlier  files,  so  the  order  in  which the logrotate config files are listed is important.
       Normally, a single config file which includes any other config files which are  needed  should  be  used.
       See below for more information on how to use the include directive to accomplish this.  If a directory is
       given on the command line, every file in that directory is used as a config file.

       If no command line arguments are given, logrotate will print version  and  copyright  information,  along
       with  a  short usage summary.  If any errors occur while rotating logs, logrotate will exit with non-zero
       status, although the state file will be updated.

OPTIONS

-f, --force
Tells logrotate to force the rotation, even if it doesn't think this is necessary. Sometimes this
is useful after adding new entries to a logrotate config file, or if old log files have been
removed by hand, as the new files will be created, and logging will continue correctly.

-d, --debug
Turn on debug mode, which means that no changes are made to the logs and the logrotate state file
is not updated. Only debug messages are printed.

-s, --state statefile
Tells logrotate to use an alternate state file. This is useful if logrotate is being run as a
different user for various sets of log files. To prevent parallel execution logrotate by default
acquires a lock on the state file, if it cannot be acquired logrotate will exit with value 3. The
default state file is /var/lib/logrotate/status. If /dev/null is given as the state file, then
logrotate will not try to write the state file.

--skip-state-lock
Do not lock the state file, for example if locking is unsupported or prohibited.

-v, --verbose
Turns on verbose mode, for example to display messages during rotation.

-l, --log file
Tells logrotate to log verbose output into the log_file. The verbose output logged to that file
is the same as when running logrotate with -v switch. The log file is overwritten on every
logrotate execution.

-m, --mail command
Tells logrotate which command to use when mailing logs. This command should accept the following
arguments:

1) the subject of the message given with '-s subject'
2) the recipient.

The command must then read a message on standard input and mail it to the recipient. The default
mail command is /usr/bin/mail.

--usage
Prints a short usage message.

-?, --help
Prints help message.

--version
Display version information.

CONFIGURATION FILE

logrotate reads everything about the log files it should be handling from the series of configuration
files specified on the command line. Each configuration file can set global options (local definitions
override global ones, and later definitions override earlier ones) and specify logfiles to rotate.
Global options do not affect preceding include directives. A simple configuration file looks like this:

# sample logrotate configuration file
compress

/var/log/messages {
rotate 5
weekly
postrotate
/usr/bin/killall -HUP syslogd
endscript
}

"/var/log/httpd/access.log" /var/log/httpd/error.log {
rotate 5
mail recipient@example.org
size 100k
sharedscripts
postrotate
/usr/bin/killall -HUP httpd
endscript
}

/var/log/news/* {
monthly
rotate 2
olddir /var/log/news/old
missingok
sharedscripts
postrotate
kill -HUP $(cat /var/run/inn.pid)
endscript
nocompress
}

~/log/*.log {}

The first few lines set global options; in the example, logs are compressed after they are rotated. Note
that comments may appear anywhere in the config file as long as the first non-whitespace character on the
line is a #.

Values are separated from directives by whitespace and/or an optional =. Numbers must be specified in a
format understood by strtoul(3).

The next section of the config file defines how to handle the log file /var/log/messages. The log will
go through five weekly rotations before being removed. After the log file has been rotated (but before
the old version of the log has been compressed), the command /usr/bin/killall -HUP syslogd will be
executed.

The next section defines the parameters for both /var/log/httpd/access.log and /var/log/httpd/error.log.
Each is rotated whenever it grows over 100 kilobytes in size, and the old logs files are mailed
(uncompressed) to recipient@example.org after going through 5 rotations, rather than being removed. The
sharedscripts means that the postrotate script will only be run once (after the old logs have been
compressed), not once for each log which is rotated. Note that log file names may be enclosed in quotes
(and that quotes are required if the name contains spaces). Normal shell quoting rules apply, with ', ",
and \ characters supported.

The next section defines the parameters for all of the files in /var/log/news. Each file is rotated on a
monthly basis.

The last section uses tilde expansion to rotate log files in the home directory of the current user.
This is only available, if your glob library supports tilde expansion. GNU glob does support this.

Please use wildcards with caution. If you specify *, logrotate will rotate all files, including
previously rotated ones. A way around this is to use the olddir directive or a more exact wildcard (such
as *.log).

Please note, by default when using systemd(1), the option ProtectSystem=full is set in the
logrotate.service file. This prevents logrotate from modifying logs in /etc and /usr.

Here is more information on the directives which may be included in a logrotate configuration file:

CONFIGURATION FILE DIRECTIVES

These directives may be included in a logrotate configuration file:

Rotation
rotate count
Log files are rotated count times before being removed or mailed to the address specified in a
mail directive. If count is 0, old versions are removed rather than rotated. If count is -1, old
logs are not removed at all, except they are affected by maxage (use with caution, may waste
performance and disk space). Default is 0.

olddir directory
Logs are moved into directory for rotation. The directory must be on the same physical device as
the log file being rotated, unless copy, copytruncate or renamecopy option is used. The directory
is assumed to be relative to the directory holding the log file unless an absolute path name is
specified. When this option is used all old versions of the log end up in directory. This option
may be overridden by the noolddir option.

noolddir
Logs are rotated in the directory they normally reside in (this overrides the olddir option).

su user group
Rotate log files set under this user and group instead of using default user/group (usually root).
user specifies the user used for rotation and group specifies the group used for rotation (see the
section USER AND GROUP for details). If the user/group you specify here does not have sufficient
privilege to make files with the ownership you've specified in a create directive, it will cause
an error. If logrotate runs with root privileges, it is recommended to use the su directive to
rotate files in directories that are directly or indirectly in control of non-privileged users.

Frequency
hourly Log files are rotated every hour. Note that usually logrotate is configured to be run by cron
daily (or by logrotate.timer when using systemd(1)). You have to change this configuration and
run logrotate hourly to be able to really rotate logs hourly.

daily Log files are rotated every day.

weekly [weekday]
Log files are rotated once each weekday, or if the date is advanced by at least 7 days since the
last rotation (while ignoring the exact time). The weekday interpretation is following: 0 means
Sunday, 1 means Monday, ..., 6 means Saturday; the special value 7 means each 7 days,
irrespectively of weekday. Defaults to 0 if the weekday argument is omitted.

monthly
Log files are rotated the first time logrotate is run in a month (this is normally on the first
day of the month).

yearly Log files are rotated if the current year is not the same as the last rotation.

size size
Log files are rotated only if they grow bigger than size bytes. If size is followed by k, the
size is assumed to be in kilobytes. If M is used, the size is in megabytes, and if G is used, the
size is in gigabytes. So size 100, size 100k, size 100M and size 100G are all valid. This option
is mutually exclusive with the time interval options, and it causes log files to be rotated
without regard for the last rotation time, if specified after the time criteria (the last
specified option takes the precedence).

File selection
missingok
If the log file is missing, go on to the next one without issuing an error message. See also
nomissingok.

nomissingok
If a log file does not exist, issue an error. This is the default.

ifempty
Rotate the log file even if it is empty, overriding the notifempty option (ifempty is the
default).

notifempty
Do not rotate the log if it is empty (this overrides the ifempty option).

minage count
Do not rotate logs which are less than <count> days old.

maxage count
Remove rotated logs older than <count> days. The age is only checked if the logfile is to be
rotated. rotate -1 does not hinder removal. The files are mailed to the configured address if
maillast and mail are configured.

minsize size
Log files are rotated when they grow bigger than size bytes, but not before the additionally
specified time interval (daily, weekly, monthly, or yearly). The related size option is similar
except that it is mutually exclusive with the time interval options, and it causes log files to be
rotated without regard for the last rotation time, if specified after the time criteria (the last
specified option takes the precedence). When minsize is used, both the size and timestamp of a
log file are considered.

maxsize size
Log files are rotated when they grow bigger than size bytes even before the additionally specified
time interval (daily, weekly, monthly, or yearly). The related size option is similar except that
it is mutually exclusive with the time interval options, and it causes log files to be rotated
without regard for the last rotation time, if specified after the time criteria (the last
specified option takes the precedence). When maxsize is used, both the size and timestamp of a
log file are considered.

tabooext [+] list
The current taboo extension list is changed (see the include directive for information on the
taboo extensions). If a + precedes the list of extensions, the current taboo extension list is
augmented, otherwise it is replaced. At startup, the taboo extension list ,v, .cfsaved,
.disabled, .dpkg-bak, .dpkg-del, .dpkg-dist, .dpkg-new, .dpkg-old, .rhn-cfg-tmp-*, .rpmnew,
.rpmorig, .rpmsave, .swp, .ucf-dist, .ucf-new, .ucf-old, ~

taboopat [+] list
The current taboo glob pattern list is changed (see the include directive for information on the
taboo extensions and patterns). If a + precedes the list of patterns, the current taboo pattern
list is augmented, otherwise it is replaced. At startup, the taboo pattern list is empty.

Files and Folders
create mode owner group, create owner group
Immediately after rotation (before the postrotate script is run) the log file is created (with the
same name as the log file just rotated). mode specifies the mode for the log file in octal (the
same as chmod(2)), owner specifies the user who will own the log file, and group specifies the
group the log file will belong to (see the section USER AND GROUP for details). Any of the log
file attributes may be omitted, in which case those attributes for the new file will use the same
values as the original log file for the omitted attributes. This option can be disabled using the
nocreate option.

nocreate
New log files are not created (this overrides the create option).

createolddir mode owner group
If the directory specified by olddir directive does not exist, it is created. mode specifies the
mode for the olddir directory in octal (the same as chmod(2)), owner specifies the user who will
own the olddir directory, and group specifies the group the olddir directory will belong to (see
the section USER AND GROUP
for details). This option can be disabled using the nocreateolddir option.

nocreateolddir
olddir directory is not created by logrotate when it does not exist.

copy Make a copy of the log file, but don't change the original at all. This option can be used, for
instance, to make a snapshot of the current log file, or when some other utility needs to truncate
or parse the file. When this option is used, the create option will have no effect, as the old
log file stays in place. The copy option allows storing rotated log files on the different
devices using olddir directive.

nocopy Do not copy the original log file and leave it in place. (this overrides the copy option).

copytruncate
Truncate the original log file to zero size in place after creating a copy, instead of moving the
old log file and optionally creating a new one. It can be used when some program cannot be told
to close its logfile and thus might continue writing (appending) to the previous log file forever.
Note that there is a very small time slice between copying the file and truncating it, so some
logging data might be lost. When this option is used, the create option will have no effect, as
the old log file stays in place. The copytruncate option allows storing rotated log files on the
different devices using olddir directive. The copytruncate option implies norenamecopy.

nocopytruncate
Do not truncate the original log file in place after creating a copy (this overrides the
copytruncate option).

renamecopy
Log file is renamed to temporary filename in the same directory by adding ".tmp" extension to it.
After that, postrotate script is run and log file is copied from temporary filename to final
filename. In the end, temporary filename is removed. The renamecopy option allows storing
rotated log files on the different devices using olddir directive. The renamecopy option implies
nocopytruncate.

norenamecopy
Do not rename and copy the original log file (this overrides the renamecopy option).

shred Delete log files using shred -u instead of unlink(). This should ensure that logs are not
readable after their scheduled deletion; this is off by default. See also noshred.

noshred
Do not use shred when deleting old log files. See also shred.

shredcycles count
Asks GNU shred(1) to overwrite log files count times before deletion. Without this option,
shred's default will be used.

allowhardlink
Rotate files with multiple hard links; this is off by default. The target file might get emptied,
e.g. with shred or copytruncate. Use with caution, especially when the log files are rotated as
root.

noallowhardlink
Do not rotate files with multiple hard links. See also allowhardlink.

Compression
compress
Old versions of log files are compressed with gzip(1) by default. See also nocompress.

nocompress
Old versions of log files are not compressed. See also compress.

compresscmd
Specifies which command to use to compress log files. The default is gzip(1). See also compress.

uncompresscmd
Specifies which command to use to uncompress log files. The default is gunzip(1).

compressext
Specifies which extension to use on compressed logfiles, if compression is enabled. The default
follows that of the configured compression command.

compressoptions
Command line options may be passed to the compression program, if one is in use. The default, for
gzip(1), is "-6" (biased towards high compression at the expense of speed). If you use a
different compression command, you may need to change the compressoptions to match.

delaycompress
Postpone compression of the previous log file to the next rotation cycle. This only has effect
when used in combination with compress. It can be used when some program cannot be told to close
its logfile and thus might continue writing to the previous log file for some time.

nodelaycompress
Do not postpone compression of the previous log file to the next rotation cycle (this overrides
the delaycompress option).

Filenames
extension ext
Log files with ext extension can keep it after the rotation. If compression is used, the
compression extension (normally .gz) appears after ext. For example you have a logfile named
mylog.foo and want to rotate it to mylog.1.foo.gz instead of mylog.foo.1.gz.

addextension ext
Log files are given the final extension ext after rotation. If the original file already ends
with ext, the extension is not duplicated, but merely moved to the end, that is both filename and
filenameext would get rotated to filename.1ext. If compression is used, the compression extension
(normally .gz) appears after ext.

start count
This is the number to use as the base for rotation. For example, if you specify 0, the logs will
be created with a .0 extension as they are rotated from the original log files. If you specify 9,
log files will be created with a .9, skipping 0–8. Files will still be rotated the number of
times specified with the rotate directive.

dateext
Archive old versions of log files adding a date extension like YYYYMMDD instead of simply adding a
number. The extension may be configured using the dateformat and dateyesterday options.

nodateext
Do not archive old versions of log files with date extension (this overrides the dateext option).

dateformat format_string
Specify the extension for dateext using the notation similar to strftime(3) function. Only %Y %m
%d %H %M %S %V and %s specifiers are allowed. The default value is -%Y%m%d except hourly, which
uses -%Y%m%d%H as default value. Note that also the character separating log name from the
extension is part of the dateformat string. The system clock must be set past Sep 9th 2001 for %s
to work correctly. Note that the datestamps generated by this format must be lexically sortable
(that is first the year, then the month then the day. For example 2001/12/01 is ok, but
01/12/2001 is not, since 01/11/2002 would sort lower while it is later). This is because when
using the rotate option, logrotate sorts all rotated filenames to find out which logfiles are
older and should be removed.

dateyesterday
Use yesterday's instead of today's date to create the dateext extension, so that the rotated log
file has a date in its name that is the same as the timestamps within it.

datehourago
Use hour ago instead of current date to create the dateext extension, so that the rotated log file
has a hour in its name that is the same as the timestamps within it. Useful with rotate hourly.

Mail
mail address
When a log is rotated out of existence, it is mailed to address. If no mail should be generated
by a particular log, the nomail directive may be used.

nomail Do not mail old log files to any address.

mailfirst
When using the mail command, mail the just-rotated file, instead of the about-to-expire file.

maillast
When using the mail command, mail the about-to-expire file, instead of the just-rotated file (this
is the default).

Additional config files
include file_or_directory
Reads the file given as an argument as if it was included inline where the include directive
appears. If a directory is given, most of the files in that directory are read in alphabetic
order before processing of the including file continues. The only files which are ignored are
files which are not regular files (such as directories and named pipes) and files whose names end
with one of the taboo extensions or patterns, as specified by the tabooext or taboopat directives,
respectively. The given path may start with ~/ to make it relative to the home directory of the
executing user. For security reasons configuration files must not be group-writable nor world-
writable.

Scripts
sharedscripts
Normally, prerotate and postrotate scripts are run for each log which is rotated and the absolute
path to the log file is passed as first argument to the script. That means a single script may be
run multiple times for log file entries which match multiple files (such as the /var/log/news/*
example). If sharedscripts is specified, the scripts are only run once, no matter how many logs
match the wildcarded pattern, and whole pattern is passed to them. However, if none of the logs
in the pattern require rotating, the scripts will not be run at all. If the scripts exit with
error (or any log fails to rotate), the remaining actions will not be executed for any logs. This
option overrides the nosharedscripts option.

nosharedscripts
Run prerotate and postrotate scripts for every log file which is rotated (this is the default, and
overrides the sharedscripts option). The absolute path to the log file is passed as first
argument to the script. The absolute path to the final rotated log file is passed as the second
argument to the postrotate script. If the scripts exit with error, the remaining actions will not
be executed for the affected log only.

firstaction
script
endscript
The script is executed once before all log files that match the wildcarded pattern are rotated,
before the prerotate script is run and only if at least one log will actually be rotated. These
directives may only appear inside a log file definition. The whole pattern is passed to the
script as its first argument. If the script exits with an error, no further processing is done.
See also lastaction and the SCRIPTS section.

lastaction
script
endscript
The script is executed once after all log files that match the wildcarded pattern are rotated,
after the postrotate script is run and only if at least one log is rotated. These directives may
only appear inside a log file definition. The whole pattern is passed to the script as its first
argument. If the script exits with an error, just an error message is shown (as this is the last
action). See also firstaction and the SCRIPTS section.

prerotate
script
endscript
The script is executed before the log file is rotated and only if the log will actually be
rotated. These directives may only appear inside a log file definition. Normally, the absolute
path to the log file is passed as the first argument to the script. If sharedscripts is
specified, the whole pattern is passed to the script. See also postrotate and the SCRIPTS
section. See sharedscripts and nosharedscripts for error handling.

postrotate
script
endscript
The script is executed after the log file is rotated. These directives may only appear inside a
log file definition. Normally, the absolute path to the log file is passed as the first argument
to the script and the absolute path to the final rotated log file is passed as the second argument
to the script. If sharedscripts is specified, the whole pattern is passed as the first argument
to the script, and the second argument is omitted. See also prerotate and the SCRIPTS section.
See sharedscripts and nosharedscripts for error handling.

preremove
script
endscript
The script is executed once just before removal of a log file. logrotate will pass the name of
file which is soon to be removed as the first argument to the script. See also firstaction and the
SCRIPTS section.

SCRIPTS

       The lines between the starting keyword (e.g. prerotate) and endscript (both of which must appear on lines
       by themselves) are executed (using /bin/sh).  The script inherits some traits from the logrotate process,
       including stderr, stdout, the current directory, the environment, and the umask.  Scripts are run as  the
       invoking  user  and  group,  irrespective  of  any  su  directive.  If the --log flag was specified, file
       descriptor 3 is the log file.  The current working directory is unspecified.

USER AND GROUP

       User and group identifiers are resolved first by trying the textual representation and, in case it fails,
       afterwards by the numeric value.

FILES

       /var/lib/logrotate/status   Default state file.
       /etc/logrotate.conf         Configuration options.

AUTHORS

       Erik Troan, Preston Brown, Jan Kaluza.

       <https://github.com/logrotate/logrotate>