Criando uma rotação de arquivo de log no Linux com logrotate

Olá, meu caro!

O logrotate já é o responsável por administrar os logs de muitas aplicações, se você for até a pasta onde  estão as configurações e listar, verá algo como na saída abaixo:

[root@master logrotate.d]# cd /etc/logrotate.d/
[root@master logrotate.d]# ls -la
total 72
drwxr-xr-x.   2 root root  249 May 11 06:24 .
drwxr-xr-x. 141 root root 8192 Jun 11 16:19 ..
-rw-r--r--    1 root root   91 Nov 27  2019 bootlog
-rw-r--r--.   1 root root  160 Sep 19  2018 chrony
-rw-r--r--    1 root root  194 Nov 27  2019 httpd
-rw-r--r--    1 root root  172 Sep 29  2016 iscsiuiolog
-rw-r--r--    1 root root  165 Apr  1 00:31 libvirtd
-rw-r--r--    1 root root  142 Apr  1 00:31 libvirtd.qemu
-rw-r--r--    1 root root  893 Apr  2 14:51 mariadb
-rw-r--r--    1 root root  106 Apr 10  2018 numad
-rw-r--r--.   1 root root  408 Aug  3  2017 psacct
-rw-r--r--    1 root root  115 Apr  2 10:24 samba
-rw-r--r--    1 root root   71 Apr  2 10:17 subscription-manager
-rw-r--r--    1 root root  224 Nov 27  2019 syslog
-rw-r--r--    1 root root   32 Dec  9  2013 up2date
-rw-r--r--.   1 root root  100 Oct 30  2018 wpa_supplicant
-rw-r--r--    1 root root  103 Apr  2 12:56 yum

/var/www/logs/*.log {
    daily
    missingok
    dateext
    dateformat _%Y-%m-%d
    dateyesterday
    rotate 90
    compress
    delaycompress
    compressext
    notifempty
    create 0640 www-data www-data
    sharedscripts
    postrotate
           [ -f /var/run/nginx.pid ] && kill -USR1 `cat /var/run/nginx.pid`
    endscript
    
  
[root@master logrotate.d]#  cd /etc/logrotate.d/
[root@master logrotate.d]#  touch securelog
[root@master logrotate.d]#  chmod 644 securelog; chown root:root securelog
[root@master logrotate.d]#  vi securelog

/var/log/secure.log
{
daily
maxsize 100M
rotate 4
}

Arquivos padrões do logrotate

/var/lib/logrotate.status

/etc/logrotate.conf

Arquivos de configurações do logrotate de amostra

/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 www@my.org
    size 100k
    sharedscripts
    postrotate
        /usr/bin/killall -HUP httpd
    endscript
}

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

Detalhe de cada opção que pode ser utilizada com o logrotate

compress

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

compresscmd

Specifies which command to use to compress log files. The default is gzip. See also compress.

uncompresscmd

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

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 "-9" (maximum compression).

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.

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.

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 /bin/sh) 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 /bin/sh) 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 /bin/sh) 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 /bin/sh) 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 only if they grow bigger then 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 100Gare 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 /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, 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 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.

shredcycles count

Asks GNU shred(1) to overwite log files count times before deletion. Without this option, shred's default 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.

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 contains .rpmorig, .rpmsave, ,v, .swp, .rpmnew, ~, .cfsaved and .rhn-cfg-tmp-*.

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.