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NEWSYSLOG(8)                System Manager's Manual               NEWSYSLOG(8)

     newsyslog, newsyslog.conf - maintain system log files to manageable sizes

     newsyslog [-Fnrsv] [-f config_file] [file ...]

     newsyslog is a program that should be scheduled to run periodically by
     cron(8).  When it is executed it archives log files if necessary.  If a
     log file is determined to require archiving, newsyslog rearranges the
     files so that "logfile" is empty, "logfile.0" has the last period's logs
     in it, "logfile.1" has the next to last period's logs in it and so on, up
     to a user-specified number of archived logs.  Optionally the archived
     logs can be compressed to save space.

     A log can be archived for three reasons:

           1.   It is larger than the configured size (in kilobytes).

           2.   A configured number of hours have elapsed since the log was
                last archived.

           3.   The configured time for rotation of the log occurred within
                the last 60 minutes.

     The granularity of newsyslog is dependent on how often it is scheduled to
     run by cron(8).  It is recommended that newsyslog be run once hourly.

     When starting up, newsyslog reads in a configuration file to determine
     which logs may potentially be archived.  By default, this configuration
     file is /etc/newsyslog.conf.  Each line of the file contains information
     about a particular log file that should be handled by newsyslog.  Each
     line has six mandatory fields and three optional fields, with whitespace
     separating each field.  Blank lines or lines beginning with `#' are
     ignored.  The fields of the configuration file are as follows:

                 Name of the system log file to be archived.

                 This optional field specifies the owner and group for the
                 archive file.  The `:' is essential, even if the owner or
                 group field is left blank.  The field may be numeric, or a
                 name which is present in /etc/passwd or /etc/group.  For
                 backward compatibility, `.' is usable in lieu of `:', however
                 use of this feature is discouraged.

     mode        Specify the mode of the log file and archives.

     ngen        Specify the number of archive files to be kept besides the
                 log file itself.

     size        When the size of the log file reaches size kilobytes, the log
                 file will be trimmed as described above.  If this field is
                 replaced by an asterisk (`*'), then the size of the log file
                 is not taken into account when determining when to trim the
                 log file.

     when        The when field can consist of an interval, a specific time,
                 or both.  If the when field is an asterisk (`*') log rotation
                 will depend only on the contents of the size field.
                 Otherwise, the when field consists of an optional interval in
                 hours, optionally followed by an `@'-sign and a time in a
                 restricted ISO 8601 format or by an `$'-sign and a time
                 specification for logfile rotation at a fixed time once per
                 day, per week or per month.

                 If a time is specified, the log file will only be trimmed if
                 newsyslog is run within one hour of the specified time.  If
                 an interval is specified, the log file will be trimmed if
                 that many hours have passed since the last rotation.  When
                 both a time and an interval are specified, the log will be
                 trimmed if either condition is met.

                 There is no provision for specification of a timezone.  There
                 is little point in specifying an explicit minutes or seconds
                 component in the current implementation, since the only
                 comparison is `within the hour'.

                 ISO 8601 restricted time format

                 The lead-in character for a restricted ISO 8601 time is an
                 `@'-sign.  The particular format of the time in restricted
                 ISO 8601 is: [[[[[cc]yy]mm]dd][T[hh[mm[ss]]]]].  Optional
                 date fields default to the appropriate component of the
                 current date; optional time fields default to midnight; hence
                 if today is January 22, 1999, the following date
                 specifications are all equivalent:


                 Day, week and month time format

                 The lead-in character for day, week and month specification
                 is a `$'-sign.  The particular format of day, week and month
                 specification is: [Dhh], [Ww[Dhh]] and [Mdd[Dhh]]
                 respectively.  Optional time fields default to midnight.  The
                 ranges for day and hour specifications are:

                       hh      hours, range 0 ... 23
                       w       day of week, range 0 ... 6, 0 = Sunday
                       dd      day of month, range 1 ... 31, or the letter `L'
                               or `l' to specify the last day of the month.

                 Some examples:

                       $D0     rotate every night at midnight
                       $D23    rotate every day at 23:00 hr
                       $W0D23  rotate every week on Sunday at 23:00 hr
                       $W5D16  rotate every week on Friday at 16:00 hr
                       $MLD0   rotate at the last day of every month at
                       $M5D6   rotate on every 5th day of month at 6:00 hr

     flags       This field specifies any special processing that is required.
                 These flags are parsed in a case insensitive manner.
                 Individual flags and their meanings:

                 -       This flag means nothing -- it is used as a spacer
                         when no flags are set.

                 b       The file is a binary file or is not in syslogd(8)
                         format: the ASCII message which newsyslog inserts to
                         indicate that the logs have been trimmed should not
                         be included.

                 c       Create an empty log file if none currently exists.

                 e       Do not rotate log file with zero size (empty).  This
                         flag is mostly usable in conjunction with b flag that
                         prevents newsyslog from inserting an ASCII
                         informational message.

                 j       Archived log files should be compressed with bzip2(1)
                         to save space.

                 n       No signal should be sent when the log is trimmed.

                 p       The first historical log file (i.e. the historical
                         log file with the suffix `.0') should not be

                 x       Archived log files should be compressed with xz(1) to
                         save space.

                 z       Archived log files should be compressed with gzip(1)
                         to save space.

                 This optional field specifies the file name to read to find
                 the daemon process id.  If this field is missing, it defaults
                 to the /var/run/syslogd.pid file.  A signal of type sigtype
                 is sent to the process id contained in this path_to_pid_file
                 file.  This field must start with `/' in order to be
                 recognized properly.

     sigtype     This optional field specifies the type of signal to be sent
                 to the daemon process.  This may be a numeric or symbolic
                 value.  By default a SIGHUP (hang-up) will be sent.

     The following options can be used with newsyslog:

     -F      Force trimming of the logs, even if the trim conditions have not
             been met.  This option is useful for diagnosing system problems
             by providing you with fresh logs.

     -f config_file
             Use config_file instead of /etc/newsyslog.conf as the
             configuration file.

     -n      Do not trim the logs, but print out what would be done if this
             option were not specified: -n implies -v.

     -r      Remove the restriction that newsyslog must be running as root.
             When running as a regular user, newsyslog will not be able to
             send a SIGHUP signal to syslogd(8), so this option should be used
             only when debugging or trimming user generated logs.

     -s      Do not signal daemon processes.

     -v      Run in verbose mode.  In this mode each action that is taken will
             be printed.

     If additional command line arguments are given, newsyslog will only
     examine log files that match those arguments; otherwise, it will examine
     all files listed in the configuration file.

     /etc/newsyslog.conf      newsyslog configuration file.

     bzip2(1), gzip(1), syslog(3), syslogd(8)

NetBSD 10.99                     March 1, 2021                    NetBSD 10.99