freebsd-skq/usr.sbin/newsyslog/newsyslog.conf.5
Juraj Lutter c7d27b225d newsyslog(8): Implement a new 'E' flag to not rotate empty log files
Based on an idea from dvl's coworker, László DANIELISZ, implement
a new flag, 'E', that prevents newsyslog(8) from rotating the empty
log files. This 'E' flag ist mostly usable in conjunction with 'B'
flag that instructs newsyslog(8) to not insert an informational
message into the log file after rotation, keeping it still empty.

Reviewed by:	markj, ian, manpages (rpokala)
Approved by:	markj, ian, manpages (rpokala)
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D28940
2021-02-28 23:32:19 +01:00

436 lines
11 KiB
Groff

.\" This file was split from the newsyslog(8) manual page by Tom Rhodes
.\" and includes modifications as appropriate.
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.\" This file contains changes from the Open Software Foundation.
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.\" from: @(#)newsyslog.8
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.Dd February 26, 2021
.Dt NEWSYSLOG.CONF 5
.Os
.Sh NAME
.Nm newsyslog.conf
.Nd
.Xr newsyslog 8
configuration file
.Sh DESCRIPTION
The
.Nm
file is used to set log file rotation configuration for the
.Xr newsyslog 8
utility.
Configuration may designate that logs are rotated based on
size, last rotation time, or time of day.
The
.Nm
file can also be used to designate secure permissions to log
files at rotation time.
During initialization,
.Xr newsyslog 8
reads a configuration file,
normally
.Pa /etc/newsyslog.conf ,
to determine which logs may potentially be rotated and archived.
Each line has five mandatory fields and four optional fields,
separated with whitespace.
Blank lines or lines beginning with
.Ql #
are ignored.
If
.Ql #
is placed in the middle of the line, the
.Ql #
character and the rest of the line after it is ignored.
To prevent special meaning, the
.Ql #
character may be escaped with
.Ql \e ;
in this case preceding
.Ql \e
is removed and
.Ql #
is treated as an ordinary character.
The fields of the configuration file are as follows:
.Bl -tag -width indent
.It Ar logfile_name
Name of the system log file to be archived,
or one of the literal strings
.Dq Aq Li default ,
or
.Dq Aq Li include .
The special default entry will only be used if a log file
name is given as a command line argument to
.Xr newsyslog 8 ,
and if that log file name is not matched by any other
line in the configuration file.
The include entry is used to include other configuration
files and supports globbing.
.It Ar owner : Ns Ar group
This optional field specifies the owner and group for the archive file.
The
.Ql \&:
is essential regardless if the
.Ar owner
or
.Ar group
field is left blank or contains a value.
The field may be numeric, or a name which is present in
.Pa /etc/passwd
or
.Pa /etc/group .
.It Ar mode
Specify the file mode of the log file and archives.
Valid mode bits are
.Dv 0666 .
(That is, read and write permissions for the rotated log may be specified for
the owner, group, and others.)
All other mode bits are ignored.
.It Ar count
Specify the maximum number of archive files which may exist.
This does not consider the current log file.
.It Ar size
When the size of the log file reaches
.Ar size
in kilobytes, the log file will be trimmed as described above.
If this field contains an asterisk
.Pq Ql * ,
the log file will not be trimmed based on size.
.It Ar when
The
.Ar when
field may consist of an interval, a specific time, or both.
If the
.Ar when
field contains an asterisk
.Pq Ql * ,
log rotation will solely depend on the contents of the
.Ar size
field.
Otherwise, the
.Ar when
field consists of an optional interval in hours, usually followed
by an
.So Li \&@ Sc Ns No -sign
and a time in restricted
.Tn ISO 8601
format.
Additionally, the format may also be constructed with a
.Ql $
sign along with a rotation time specification of once
a day, once a week, or once a month.
.Pp
Time based trimming happens only if
.Xr newsyslog 8
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 then both conditions must be satisfied for the rotation to
take place.
.Pp
There is no provision for the 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
.Dq within the hour .
.Pp
.Sy ISO 8601 restricted time format :
.Pp
The lead-in character for a restricted
.Tn ISO 8601
time is an
.Ql @
sign.
The particular format of the time in restricted
.Tn ISO 8601
is:
.Sm off
.Oo Oo Oo Oo Oo
.Va cc Oc
.Va yy Oc
.Va mm Oc
.Va dd Oc
.Oo
.Li T Oo
.Va hh Oo
.Va mm Oo
.Va ss
.Oc Oc Oc Oc Oc .
.Sm on
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:
.Pp
.Bl -item -compact -offset indent
.It
.Sq Li 19990122T000000
.It
.Sq Li 990122T000000
.It
.Sq Li 0122T000000
.It
.Sq Li 22T000000
.It
.Sq Li T000000
.It
.Sq Li T0000
.It
.Sq Li T00
.It
.Sq Li 22T
.It
.Sq Li T
.It
.Sq Li \&
.El
.Pp
.Sy Day, week, and month time format:
.Pp
The lead-in character for day, week, and month specification is a
.Ql $
sign.
The particular format of day, week, and month specification is:
.Op Li D Ns Va hh ,
.Op Li W Ns Va w Ns Op Li D Ns Va hh ,
and
.Op Li M Ns Va dd Ns Op Li D Ns Va hh ,
respectively.
Optional time fields default to midnight.
The ranges for day and hour specifications are:
.Pp
.Bl -tag -width indent -offset indent -compact
.It Ar hh
hours, range 0..23
.It Ar w
day of week, range 0..6, 0 = Sunday
.It Ar dd
day of month, range 1..31, or one of the letters
.Ql L
or
.Ql l
to specify the last day of the month.
.El
.Pp
Some examples:
.Pp
.Bl -tag -width indent -offset indent -compact
.It Li $D0
rotate every night at midnight
(same as
.Li @T00 )
.It Li $D23
rotate every day at 23:00
(same as
.Li @T23 )
.It Li $W0D23
rotate every week on Sunday at 23:00
.It Li $W5D16
rotate every week on Friday at 16:00
.It Li $M1D0
rotate at the first day of every month at midnight
(i.e., the start of the day; same as
.Li @01T00 )
.It Li $M5D6
rotate on every fifth day of month at 6:00
(same as
.Li @05T06 )
.El
.It Ar flags
This optional field is made up of one or more characters
that specify any special processing to be done for the log
files matched by this line.
The following are valid flags:
.Bl -tag -width indent
.It Cm B
indicates that the log file is a binary file, or has some
special format.
Usually
.Xr newsyslog 8
inserts an
.Tn ASCII
message into a log file during rotation.
This message is used to indicate
when, and sometimes why the log file was rotated.
If
.Cm B
is specified, then that informational message will not be
inserted into the log file.
.It Cm C
indicates that the log file should be created if it does not
already exist, and if the
.Fl C
option was also specified on the command line.
.It Cm D
indicates that
.Xr newsyslog 8
should set the
.Dv UF_NODUMP
flag when creating a new version of
this log file.
This option would affect how the
.Xr dump 8
command treats the log file when making a file system backup.
.It Cm E
indicates that the log file should not be rotated when its
size is zero.
The
.Cm E
flag is mostly useful in conjunction with
.Cm B
flag to prevent
.Xr newsyslog 8
from inserting an informational
.Tn ASCII
message into the new file.
.It Cm G
indicates that the specified
.Ar logfile_name
is a shell pattern, and that
.Xr newsyslog 8
should archive all filenames matching that pattern using the
other options on this line.
See
.Xr glob 3
for details on syntax and matching rules.
.It Cm J
indicates that
.Xr newsyslog 8
should attempt to save disk space by compressing the rotated
log file using
.Xr bzip2 1 .
.It Cm N
indicates that there is no process which needs to be signaled
when this log file is rotated.
.It Cm p
indicates that the zero-th rotated file should not be compressed.
.It Cm R
if this flag is set the
.Xr newsyslog 8
will run shell command defined in
.Ar path_to_pid_cmd_file
after rotation instead of trying to send signal to a process id
stored in the file.
.It Cm T
if this flag is set the informational rotation message written to
the log file will be in the format specified by RFC5424.
Normally, the rotation message is written in the traditional (RFC3164)
syslog format.
.It Cm U
indicates that the file specified by
.Ar path_to_pid_cmd_file
will contain the ID for a process group instead of a process.
This option also requires that the first line in that file
be a negative value to distinguish it from a process ID.
.It Cm X
indicates that
.Xr newsyslog 8
should attempt to save disk space by compressing the rotated
log file using
.Xr xz 1 .
.It Cm Y
indicates that
.Xr newsyslog 8
should attempt to save disk space by compressing the rotated
log file using
.Xr zstd 1 .
.It Cm Z
indicates that
.Xr newsyslog 8
should attempt to save disk space by compressing the rotated
log file using
.Xr gzip 1 .
.It Fl
a minus sign will not cause any special processing, but it
can be used as a placeholder to create a
.Ar flags
field when you need to specify any of the following fields.
.El
.It Ar path_to_pid_cmd_file
This optional field specifies the file name containing a daemon's
process ID or to find a group process ID if the
.Cm U
flag was specified.
If this field is present, a
.Ar signal
is sent to the process ID contained in this file.
If this field is not present and the
.Cm N
flag has not been specified, then a
.Dv SIGHUP
signal will be sent to
.Xr syslogd 8
or to the process id found in the file specified by
.Xr newsyslog 8 Ns 's
.Fl S
switch.
This field must start with
.Ql /
in order to be recognized properly.
When used with the
.Cm R
flag, the file is treated as a path to a binary to be executed
by the
.Xr newsyslog 8
after rotation instead of sending the signal out.
.It Ar signal
This optional field specifies the signal that will be sent to the daemon
process (or to all processes in a process group, if the
.Cm U
flag was specified).
If this field is not present, then a
.Dv SIGHUP
signal will be sent.
Signal names
must start with
.Dq SIG
and be the signal name, e.g.,
.Dv SIGUSR1 .
Alternatively,
.Ar signal
can be the signal number, e.g., 30 for
.Dv SIGUSR1 .
.El
.Sh EXAMPLES
The following is an example of the
.Dq Aq Li include
entry:
.Dl "<include> /etc/newsyslog-local.conf"
.Sh SEE ALSO
.Xr bzip2 1 ,
.Xr gzip 1 ,
.Xr xz 1 ,
.Xr syslog 3 ,
.Xr chown 8 ,
.Xr newsyslog 8 ,
.Xr syslogd 8
.Pp
.Rs
.%A C. Lonvick
.%T The BSD syslog Protocol
.%O RFC3164
.Re
.Rs
.%A R. Gerhards
.%T The Syslog Protocol
.%O RFC5424
.Re
.Sh HISTORY
This manual page first appeared in
.Fx 4.10 .