файлы конфигурации службы журнала (Journal service configuration files)
Параметры (Options)
All options are configured in the [Journal] section:
Storage=
Controls where to store journal data. One of "volatile",
"persistent", "auto" and "none". If "volatile", journal log
data will be stored only in memory, i.e. below the
/run/log/journal hierarchy (which is created if needed). If
"persistent", data will be stored preferably on disk, i.e.
below the /var/log/journal hierarchy (which is created if
needed), with a fallback to /run/log/journal (which is
created if needed), during early boot and if the disk is not
writable. "auto" behaves like "persistent" if the
/var/log/journal directory exists, and "volatile" otherwise
(the existence of the directory controls the storage mode).
"none" turns off all storage, all log data received will be
dropped (but forwarding to other targets, such as the
console, the kernel log buffer, or a syslog socket will still
work). Defaults to "auto" in the default journal namespace,
and "persistent" in all others.
Note that journald will initially use volatile storage, until
a call to journalctl --flush (or sending SIGUSR1 to journald)
will cause it to switch to persistent logging (under the
conditions mentioned above). This is done automatically on
boot via "systemd-journal-flush.service".
Note that when this option is changed to "volatile", existing
persistent data is not removed. In the other direction,
journalctl(1) with the --flush option may be used to move
volatile data to persistent storage.
Compress=
Can take a boolean value. If enabled (the default), data
objects that shall be stored in the journal and are larger
than the default threshold of 512 bytes are compressed before
they are written to the file system. It can also be set to a
number of bytes to specify the compression threshold
directly. Suffixes like K, M, and G can be used to specify
larger units.
Seal=
Takes a boolean value. If enabled (the default), and a
sealing key is available (as created by journalctl(1)'s
--setup-keys command), Forward Secure Sealing (FSS) for all
persistent journal files is enabled. FSS is based on Seekable
Sequential Key Generators
SplitMode=
Controls whether to split up journal files per user, either
"uid" or "none". Split journal files are primarily useful for
access control: on UNIX/Linux access control is managed per
file, and the journal daemon will assign users read access to
their journal files. If "uid", all regular users (with UID
outside the range of system users, dynamic service users, and
the nobody user) will each get their own journal files, and
system users will log to the system journal. See Users,
Groups, UIDs and GIDs on systemd systems
RateLimitIntervalSec=, RateLimitBurst=
Configures the rate limiting that is applied to all messages
generated on the system. If, in the time interval defined by
RateLimitIntervalSec=, more messages than specified in
RateLimitBurst= are logged by a service, all further messages
within the interval are dropped until the interval is over. A
message about the number of dropped messages is generated.
This rate limiting is applied per-service, so that two
services which log do not interfere with each other's limits.
Defaults to 10000 messages in 30s. The time specification for
RateLimitIntervalSec= may be specified in the following
units: "s", "min", "h", "ms", "us". To turn off any kind of
rate limiting, set either value to 0.
Note that the effective rate limit is multiplied by a factor
derived from the available free disk space for the journal.
Currently, this factor is calculated using the base 2
logarithm.
Table 1. Example RateLimitBurst= rate modifications by the
available disk space
┌─────────────────────┬──────────────────┐
│Available Disk Space │ Burst Multiplier │
├─────────────────────┼──────────────────┤
│<= 1MB │ 1 │
├─────────────────────┼──────────────────┤
│<= 16MB │ 2 │
├─────────────────────┼──────────────────┤
│<= 256MB │ 3 │
├─────────────────────┼──────────────────┤
│<= 4GB │ 4 │
├─────────────────────┼──────────────────┤
│<= 64GB │ 5 │
├─────────────────────┼──────────────────┤
│<= 1TB │ 6 │
└─────────────────────┴──────────────────┘
If a service provides rate limits for itself through
LogRateLimitIntervalSec= and/or LogRateLimitBurst= in
systemd.exec(5), those values will override the settings
specified here.
SystemMaxUse=, SystemKeepFree=, SystemMaxFileSize=,
SystemMaxFiles=, RuntimeMaxUse=, RuntimeKeepFree=,
RuntimeMaxFileSize=, RuntimeMaxFiles=
Enforce size limits on the journal files stored. The options
prefixed with "System" apply to the journal files when stored
on a persistent file system, more specifically
/var/log/journal. The options prefixed with "Runtime" apply
to the journal files when stored on a volatile in-memory file
system, more specifically /run/log/journal. The former is
used only when /var/ is mounted, writable, and the directory
/var/log/journal exists. Otherwise, only the latter applies.
Note that this means that during early boot and if the
administrator disabled persistent logging, only the latter
options apply, while the former apply if persistent logging
is enabled and the system is fully booted up. journalctl and
systemd-journald ignore all files with names not ending with
".journal" or ".journal~", so only such files, located in the
appropriate directories, are taken into account when
calculating current disk usage.
SystemMaxUse= and RuntimeMaxUse= control how much disk space
the journal may use up at most. SystemKeepFree= and
RuntimeKeepFree= control how much disk space systemd-journald
shall leave free for other uses. systemd-journald will
respect both limits and use the smaller of the two values.
The first pair defaults to 10% and the second to 15% of the
size of the respective file system, but each value is capped
to 4G. If the file system is nearly full and either
SystemKeepFree= or RuntimeKeepFree= are violated when
systemd-journald is started, the limit will be raised to the
percentage that is actually free. This means that if there
was enough free space before and journal files were created,
and subsequently something else causes the file system to
fill up, journald will stop using more space, but it will not
be removing existing files to reduce the footprint again,
either. Also note that only archived files are deleted to
reduce the space occupied by journal files. This means that,
in effect, there might still be more space used than
SystemMaxUse= or RuntimeMaxUse= limit after a vacuuming
operation is complete.
SystemMaxFileSize= and RuntimeMaxFileSize= control how large
individual journal files may grow at most. This influences
the granularity in which disk space is made available through
rotation, i.e. deletion of historic data. Defaults to one
eighth of the values configured with SystemMaxUse= and
RuntimeMaxUse=, so that usually seven rotated journal files
are kept as history.
Specify values in bytes or use K, M, G, T, P, E as units for
the specified sizes (equal to 1024, 1024², ... bytes). Note
that size limits are enforced synchronously when journal
files are extended, and no explicit rotation step triggered
by time is needed.
SystemMaxFiles= and RuntimeMaxFiles= control how many
individual journal files to keep at most. Note that only
archived files are deleted to reduce the number of files
until this limit is reached; active files will stay around.
This means that, in effect, there might still be more journal
files around in total than this limit after a vacuuming
operation is complete. This setting defaults to 100.
MaxFileSec=
The maximum time to store entries in a single journal file
before rotating to the next one. Normally, time-based
rotation should not be required as size-based rotation with
options such as SystemMaxFileSize= should be sufficient to
ensure that journal files do not grow without bounds.
However, to ensure that not too much data is lost at once
when old journal files are deleted, it might make sense to
change this value from the default of one month. Set to 0 to
turn off this feature. This setting takes time values which
may be suffixed with the units "year", "month", "week",
"day", "h" or "m" to override the default time unit of
seconds.
MaxRetentionSec=
The maximum time to store journal entries. This controls
whether journal files containing entries older than the
specified time span are deleted. Normally, time-based
deletion of old journal files should not be required as
size-based deletion with options such as SystemMaxUse= should
be sufficient to ensure that journal files do not grow
without bounds. However, to enforce data retention policies,
it might make sense to change this value from the default of
0 (which turns off this feature). This setting also takes
time values which may be suffixed with the units "year",
"month", "week", "day", "h" or " m" to override the default
time unit of seconds.
SyncIntervalSec=
The timeout before synchronizing journal files to disk. After
syncing, journal files are placed in the OFFLINE state. Note
that syncing is unconditionally done immediately after a log
message of priority CRIT, ALERT or EMERG has been logged.
This setting hence applies only to messages of the levels
ERR, WARNING, NOTICE, INFO, DEBUG. The default timeout is 5
minutes.
ForwardToSyslog=, ForwardToKMsg=, ForwardToConsole=,
ForwardToWall=
Control whether log messages received by the journal daemon
shall be forwarded to a traditional syslog daemon, to the
kernel log buffer (kmsg), to the system console, or sent as
wall messages to all logged-in users. These options take
boolean arguments. If forwarding to syslog is enabled but
nothing reads messages from the socket, forwarding to syslog
has no effect. By default, only forwarding to wall is
enabled. These settings may be overridden at boot time with
the kernel command line options
"systemd.journald.forward_to_syslog",
"systemd.journald.forward_to_kmsg",
"systemd.journald.forward_to_console", and
"systemd.journald.forward_to_wall". If the option name is
specified without "=" and the following argument, true is
assumed. Otherwise, the argument is parsed as a boolean.
When forwarding to the console, the TTY to log to can be
changed with TTYPath=, described below.
When forwarding to the kernel log buffer (kmsg), make sure to
select a suitably large size for the log buffer, for example
by adding "log_buf_len=8M" to the kernel command line.
systemd will automatically disable kernel's rate-limiting
applied to userspace processes (equivalent to setting
"printk.devkmsg=on").
MaxLevelStore=, MaxLevelSyslog=, MaxLevelKMsg=, MaxLevelConsole=,
MaxLevelWall=
Controls the maximum log level of messages that are stored in
the journal, forwarded to syslog, kmsg, the console or wall
(if that is enabled, see above). As argument, takes one of
"emerg", "alert", "crit", "err", "warning", "notice", "info",
"debug", or integer values in the range of 0–7 (corresponding
to the same levels). Messages equal or below the log level
specified are stored/forwarded, messages above are dropped.
Defaults to "debug" for MaxLevelStore= and MaxLevelSyslog=,
to ensure that the all messages are stored in the journal and
forwarded to syslog. Defaults to "notice" for MaxLevelKMsg=,
"info" for MaxLevelConsole=, and "emerg" for MaxLevelWall=.
These settings may be overridden at boot time with the kernel
command line options "systemd.journald.max_level_store=",
"systemd.journald.max_level_syslog=",
"systemd.journald.max_level_kmsg=",
"systemd.journald.max_level_console=",
"systemd.journald.max_level_wall=".
ReadKMsg=
Takes a boolean value. If enabled systemd-journal processes
/dev/kmsg messages generated by the kernel. In the default
journal namespace this option is enabled by default, it is
disabled in all others.
Audit=
Takes a boolean value. If enabled systemd-journal will turn
on kernel auditing on start-up. If disabled it will turn it
off. If unset it will neither enable nor disable it, leaving
the previous state unchanged. Note that this option does not
control whether systemd-journald collects generated audit
records, it just controls whether it tells the kernel to
generate them. This means if another tool turns on auditing
even if systemd-journald left it off, it will still collect
the generated messages. Defaults to on.
TTYPath=
Change the console TTY to use if ForwardToConsole=yes is
used. Defaults to /dev/console.
LineMax=
The maximum line length to permit when converting stream logs
into record logs. When a systemd unit's standard output/error
are connected to the journal via a stream socket, the data
read is split into individual log records at newline ("\n",
ASCII 10) and NUL characters. If no such delimiter is read
for the specified number of bytes a hard log record boundary
is artificially inserted, breaking up overly long lines into
multiple log records. Selecting overly large values increases
the possible memory usage of the Journal daemon for each
stream client, as in the worst case the journal daemon needs
to buffer the specified number of bytes in memory before it
can flush a new log record to disk. Also note that permitting
overly large line maximum line lengths affects compatibility
with traditional log protocols as log records might not fit
anymore into a single AF_UNIX or AF_INET datagram. Takes a
size in bytes. If the value is suffixed with K, M, G or T,
the specified size is parsed as Kilobytes, Megabytes,
Gigabytes, or Terabytes (with the base 1024), respectively.
Defaults to 48K, which is relatively large but still small
enough so that log records likely fit into network datagrams
along with extra room for metadata. Note that values below 79
are not accepted and will be bumped to 79.
