logrotate ‐ rotates, compresses, and mails system logs
logrotate [--force] [--debug] [--state
file] [--skip-state-lock] [--verbose] [--log
file] [--mail command] config_file
[config_file2 ...]
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.
- -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 lock or 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.
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).
Here is more information on the directives which may be included
in a logrotate configuration file:
These directives may be included in a logrotate
configuration file:
- 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.
- hourly
- Log files are rotated every hour. Note that usually logrotate is
configured to be run by cron daily. 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 the 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).
- 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.
- 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.
- 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.
- 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. This
allows storing rotated log files on the different devices using
olddir directive. In the end, temporary filename is removed.
- 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.
- 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).
- 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
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).
- 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.
- 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.
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.
User and group identifiers are resolved first by trying the
textual representation and, in case it fails, afterwards by the numeric
value.
/var/lib/logrotate/status |
Default state file. |
/etc/logrotate.conf |
Configuration options. |
Erik Troan, Preston Brown, Jan Kaluza.
<https://github.com/logrotate/logrotate>