LogRotate

The following is an adaptation of the man page for the linux version of logrotate. Differences between the two versions are noted.

logrotate - rotates, compresses, and mails system logs

Synopsis

logrotate [-dv] [-f|--force] [-s|--state file] config_file ..

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 scheduled task. It will not modify a log multiple times in one day unless the criteria for that log is based on the log's size and logrotate is being run multiple times 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.

Options

-d

Turns on debug mode and implies -v. In debug mode, no changes will be made to the logs or to the logrotate state file.

-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.

-m, --mail

Tells logrotate which command to use when mailing logs. This command should accept two arguments: 1) the subject of the message, and 2) the recipient. The command must then read a message on standard input and mail it to the recipient. The default mail command is /bin/mail -s.

The -m argument has been deprecated. Email settings are now controlled with new directives in the configuruation files.

-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. The default state file is logrotate.status located in the folder where logrotate is installed.

--usage

Prints a short usage message.

-v, --verbose

Turns on verbose mode.

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. A simple configuration file looks like this:

~~~~~~~~~~~~~~

sample logrotate configuration file

compress
smtpserver mail.mymailserver.com
smtpport 25
nosmtpssl
smtpuser username
smtpuserpwd password

c:\windows\logfiles\logfile.log {
rotate 5
weekly
prerotate
net stop service
endscript
postrotate
net start service
endscript
}

"c:\my test\log1.log" c:\test2\logfile2.log {
rotate 5
mail www@my.org
size 100k
sharedscripts
prerotate
net stop service2
endscript
postrotate
net start service2
endscript
}

"c:\program files\application**" {
# this section matches all files in all subfolders of c:\program files\application
monthly
rotate 2
olddir "c:\program files\application\oldlogs"
missingok
postrotate
c:\someprogram.exe
endscript
nocompress
}
~~~~~~~~~~~~~~~~~~~~

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

The next section of the config files defined how to handle the log file c:\windows\logfiles\logfile.log. The log will go through five weekly rotations before being removed. Before the log file is rotated, the command net stop service will be executed. After the log file has been rotated (but before the old version of the log has been compressed), the command net start service will be executed.

The next section defines the parameters for both c:\my test\log1.log and c:\test2\logfile2.log. They are rotated whenever it grows over 100k in size, and the old logs files are mailed (uncompressed) to www@my.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 the double quotes around the first filename at the beginning of this section allows logrotate to rotate logs with spaces in the name.

The last section defines the parameters for all of the files in c:\program files\application. Each file is rotated on a monthly basis. This is considered a single rotation directive and if errors occur for more than one file, the log files are not compressed.

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:

compress

Old versions of log files are compressed with zip compression by default. See also nocompress.

compresscmd

Specifies which command to use to compress log files. The default is gzip. See also compress.
This directive is deprecated. logrotate uses .Net zip compression

uncompresscmd

Specifies which command to use to uncompress log files. The default is gunzip.
This directive is deprecated.

compressext

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

compressoptions

Command line options may be passed to the compression program, if one is in use. The default, for gzip(1), is "-9" (maximum compression).
This directive is deprecated.

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.

copytruncate

Truncate the original log file 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.

create mode 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 name who will own the log file, and group specifies the group the log file will belong to. 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.

daily

Log files are rotated every day.

dateext

Archive old versions of log files adding a daily extension like YYYYMMDD instead of simply adding a number. The extension may be configured using the dateformat option.

dateformat format_string

Specify the extension for dateext using the notation similar to strftime(3) function. Only %Y %m %d and %s specifiers are allowed. The default value is -%Y%m%d. 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 (i.e., first the year, then the month then the day. e.g., 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.

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.

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.

ifempty

Rotate the log file even if it is empty, overriding the notifempty option (ifempty 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, as specified by the tabooext directive. The include directive may not appear inside a log file definition.

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. Note that this directive has no effect unless the smtpserver directive is specified (along with any other smtp directives required for email sending to work.)

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).

maxage count

Remove rotated logs older than count days. The age is only checked if the logfile is to be rotated. 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. When minsize is used, both the size and timestamp of a log file are considered.

missingok

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

monthly

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

nocompress

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

nocopy

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

nocopytruncate

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

nocreate

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

nodelaycompress

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

nodateext

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

nomail

Don't mail old log files to any address.

nomissingok

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

noolddir

Logs are rotated in the same directory the log normally resides in (this overrides the olddir 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. If the scripts exit with error, the remaining actions will not be executed for the affected log only.

noshred

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

nosmtpssl

Disables using SSL to send email. See also smtpssl.

notifempty

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

olddir directory

Logs are moved into directory for rotation. The directory must be on the same physical device as the log file being rotated, and 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.

postrotate/endscript

The lines between postrotate and endscript (both of which must appear on lines by themselves) are executed (using cmd) 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 first argument to the script. If sharedscripts is specified, whole pattern is passed to the script. See also prerotate. See sharedscripts and nosharedscripts for error handling.

prerotate/endscript

The lines between prerotate and endscript (both of which must appear on lines by themselves) are executed (using cmd) 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 first argument to the script. If sharedscripts is specified, whole pattern is passed to the script. See also postrotate. See sharedscripts and nosharedscripts for error handling.

firstaction/endscript

The lines between firstaction and endscript (both of which must appear on lines by themselves) are executed (using cmd) once before all log files that match the wildcarded pattern are rotated, before 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. Whole pattern is passed to the script as first argument. If the script exits with error, no further processing is done. See also lastaction.

lastaction/endscript

The lines between lastaction and endscript (both of which must appear on lines by themselves) are executed (using cmd) once after all log files that match the wildcarded pattern are rotated, after postrotate script is run and only if at least one log is rotated. These directives may only appear inside a log file definition. Whole pattern is passed to the script as first argument. If the script exits with error, just an error message is shown (as this is the last action). See also firstaction.

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.

size size

Log files are rotated when 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.

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 c:\program files\application* 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, the remaining actions will not be executed for any logs. This option overrides the nosharedscripts option and implies create option.

shred

Delete log files using a shredding algorithm similar to the linux shred command. This should ensure that logs are not readable after their scheduled deletion; this is off by default. See also noshred.

shredcycles count

Overwrite log files count times before deletion. Without this option, the default (3) will be used.

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 count directive.

smtpfrom fromaddress

Sets the "from" email address for emails that are sent from logwatch. The default value is "logwatch@computername" where computername is the name of the computer that logwatch is running on.

smtpport port

Sets the TCP/IP port number logwatch will connect to when sending email. The default is 25. Setting this value to 0 will disable email sending.

smtpserver hostname

Sets the hostname or IP address of the target SMTP server for sending emails. Setting this directive with no hostname defined will disable email.

smtpssl

Emails sent from logwatch will be sent using SSL. The target mail server must support SSL. This is turned off by default. See also nosmtpssl.

smtpuser username

Mail servers that require SMTP authentication have to be sent a valid username and password. This directive sets the username that will be sent. By default, no SMTP authentication will be attempted. Setting this value to something other than blank will cause SMTP authentication to be performed.

smtpuserpwd password

Mail servers that require SMTP authentication have to be sent a valid username and password. This directive sets the password that will be sent. By default, no SMTP authentication will be attempted. Note that the password is stored in clear text in the configuration file.

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. The list of extensions is seprated by spaces. At startup, the taboo extension list contains .swp.

weekly

Log files are rotated if the current weekday is less than the weekday of the last rotation or if more than a week has passed since the last rotation. This is normally the same as rotating logs on the first day of the week, but it works better if logrotate is not run every night.

yearly

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

Files

logrotate.status Default state file.
logrotate.conf

[V@no]

We have to manually create scheduling tasks for this to work, correct?
Also, what is logrotate.exe.config file in the root of installation directory?