Manual: rotatelogs

ROTATELOGS(8)						 rotatelogs					       ROTATELOGS(8)

NAME
       rotatelogs - Piped logging program to rotate Apache logs

SYNOPSIS
       rotatelogs  [  -l  ]  [ -L linkname ] [ -p program ] [ -f ] [ -D ] [ -t ] [ -v ] [ -e ] [ -c ] [ -n number-of-files ]
       logfile rotationtime|filesize(B|K|M|G) [ offset ]

SUMMARY
       rotatelogs is a simple program for use in conjunction with Apache's piped logfile feature. It supports rotation based
       on a time interval or maximum size of the log.

OPTIONS
       -l     Causes the use of local time rather than GMT as the base for the interval or for strftime(3)  formatting	with
	      size-based rotation.

       -L linkname

       -p program
	      If  given,  rotatelogs will execute the specified program every time a new log file is opened. The filename of
	      the newly opened file is passed as the first argument to the program. If executing after a rotation,  the	 old
	      log file is passed as the second argument. rotatelogs does not wait for the specified program to terminate be‐
	      fore  continuing to operate, and will not log any error code returned on termination. The spawned program uses
	      the same stdin, stdout, and stderr as rotatelogs itself, and also inherits the environment.

       -f     Causes the logfile to be opened immediately, as soon as rotatelogs starts, instead of waiting  for  the  first
	      logfile  entry  to  be  read  (for non-busy sites, there may be a substantial delay between when the server is
	      started and when the first request is handled, meaning that the associated  logfile  does	 not  "exist"  until
	      then, which causes problems from some automated logging tools)

       -D     Creates  the  parent directories of the path that the log file will be placed in if they do not already exist.
	      This allows strftime(3) formatting to be used in the path and not just the filename.

       -t     Causes the logfile to be truncated instead of rotated. This is useful when a log is processed in real time  by
	      a	 command like tail, and there is no need for archived data. No suffix will be added to the filename, however
	      format strings containing '%' characters will be respected.

       -T     Causes all but the initial logfile to be truncated when opened. This is useful when the format string contains
	      something that will loop around, such as the day of the month. Available in 2.4.56 and later.

       -v     Produce verbose output on STDERR. The output contains the result of the configuration parsing,  and  all	file
	      open and close actions.

       -e     Echo  logs  through to stdout. Useful when logs need to be further processed in real time by a further tool in
	      the chain.

       -c     Create log file for each interval, even if empty.

       -n number-of-files
	      Use a circular list of filenames without timestamps. This option overwrites log files at	startup	 and  during
	      rotation.	 With  -n 3, the series of log files opened would be "logfile", "logfile.1", "logfile.2", then over‐
	      writing "logfile". When this program first opens "logfile", the file will only be truncated if -t is also pro‐
	      vided. Every subsequent rotation will always begin with truncation of the target file. For size based rotation
	      without -t and existing log files in place, this option may result in unintuitive behavior such as initial log
	      entries being sent to "logfile.1", and entries in "logfile.1" not being preserved even  if  later	 "logfile.n"
	      have not yet been used. Available in 2.4.5 and later.

       logfile

       rotationtime
	      The time between log file rotations in seconds. The rotation occurs at the beginning of this interval. For ex‐
	      ample, if the rotation time is 3600, the log file will be rotated at the beginning of every hour; if the rota‐
	      tion  time is 86400, the log file will be rotated every night at midnight. (If no data is logged during an in‐
	      terval, no file will be created.)

       filesize(B|K|M|G)
	      The maximum file size in followed by exactly one of the letters  B  (Bytes),  K  (KBytes),  M  (MBytes)  or  G
	      (GBytes).	 .PP  When  time  and size are specified, the size must be given after the time. Rotation will occur
	      whenever either time or size limits are reached.

       offset The number of minutes offset from UTC. If omitted, zero is assumed and UTC is used. For example, to use  local
	      time in the zone UTC -5 hours, specify a value of -300 for this argument. In most cases, -l should be used in‐
	      stead of specifying an offset.

EXAMPLES
	    CustomLog "|bin/rotatelogs /var/log/logfile 86400" common

       This  creates  the  files /var/log/logfile.nnnn where nnnn is the system time at which the log nominally starts (this
       time will always be a multiple of the rotation time, so you can synchronize cron scripts with it). At the end of each
       rotation time (here after 24 hours) a new log is started.

	    CustomLog "|bin/rotatelogs -l /var/log/logfile.%Y.%m.%d 86400" common

       This creates the files /var/log/logfile.yyyy.mm.dd where yyyy is the year, mm is the month, and dd is the day of	 the
       month. Logging will switch to a new file every day at midnight, local time.

	    CustomLog "|bin/rotatelogs /var/log/logfile 5M" common

       This configuration will rotate the logfile whenever it reaches a size of 5 megabytes.

	    ErrorLog "|bin/rotatelogs /var/log/errorlog.%Y-%m-%d-%H_%M_%S 5M"

       This  configuration  will  rotate  the error logfile whenever it reaches a size of 5 megabytes, and the suffix to the
       logfile name will be created of the form errorlog.YYYY-mm-dd-HH_MM_SS.

	    CustomLog "|bin/rotatelogs -t /var/log/logfile 86400" common

       This creates the file /var/log/logfile, truncating the file at startup and then truncating the file once per day.  It
       is expected in this scenario that a separate process (such as tail) would process the file in real time.

	    CustomLog "|bin/rotatelogs -T /var/log/logfile.%d 86400" common

       If  the	server	is started (or restarted) on the first of the month, this appends to /var/log/logfile.01. When a log
       entry is written on the second of the month, /var/log/logfile.02 is truncated and new entries will be  added  to	 the
       top. This example keeps approximately 1 months worth of logs without external maintenance.

PORTABILITY
       The  following  logfile	format	string substitutions should be supported by all strftime(3) implementations, see the
       strftime(3) man page for library-specific extensions.

       • %A - full weekday name (localized)

       • %a - 3-character weekday name (localized)

       • %B - full month name (localized)

       • %b - 3-character month name (localized)

       • %c - date and time (localized)

       • %d - 2-digit day of month

       • %H - 2-digit hour (24 hour clock)

       • %I - 2-digit hour (12 hour clock)

       • %j - 3-digit day of year

       • %M - 2-digit minute

       • %m - 2-digit month

       • %p - am/pm of 12 hour clock (localized)

       • %S - 2-digit second

       • %U - 2-digit week of year (Sunday first day of week)

       • %W - 2-digit week of year (Monday first day of week)

       • %w - 1-digit weekday (Sunday first day of week)

       • %X - time (localized)

       • %x - date (localized)

       • %Y - 4-digit year

       • %y - 2-digit year

       • %Z - time zone name

       • %% - literal `%'

Apache HTTP Server					 2023-03-05					       ROTATELOGS(8)