journald.conf(5), journald.conf.d(5) - Journal service configuration files



  • JOURNALD.CONF(5)		 journald.conf		      JOURNALD.CONF(5)
    
    
    
    NAME
           journald.conf, journald.conf.d - Journal service configuration files
    
    SYNOPSIS
           /etc/systemd/journald.conf
    
           /etc/systemd/journald.conf.d/*.conf
    
           /run/systemd/journald.conf.d/*.conf
    
           /usr/lib/systemd/journald.conf.d/*.conf
    
    DESCRIPTION
           These files configure various parameters of the systemd journal
           service, systemd-journald.service(8).
    
    CONFIGURATION DIRECTORIES AND PRECEDENCE
           Default configuration is defined during compilation, so a configuration
           file is only needed when it is necessary to deviate from those
           defaults. By default the configuration file in /etc/systemd/ contains
           commented out entries showing the defaults as a guide to the
           administrator. This file can be edited to create local overrides.
    
           When packages need to customize the configuration, they can install
           configuration snippets in /usr/lib/systemd/*.conf.d/. Files in /etc/
           are reserved for the local administrator, who may use this logic to
           override the configuration files installed by vendor packages. The main
           configuration file is read before any of the configuration directories,
           and has the lowest precedence; entries in a file in any configuration
           directory override entries in the single configuration file. Files in
           the *.conf.d/ configuration subdirectories are sorted by their filename
           in lexicographic order, regardless of which of the subdirectories they
           reside in. If multiple files specify the same option, the entry in the
           file with the lexicographically latest name takes precedence. It is
           recommended to prefix all filenames in those subdirectories with a
           two-digit number and a dash, to simplify the ordering of the files.
    
           To disable a configuration file supplied by the vendor, the recommended
           way is to place a symlink to /dev/null in the configuration directory
           in /etc/, with the same filename as the vendor configuration file.
    
    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" is similar to "persistent"
    	   but the directory /var/log/journal is not created if needed, so
    	   that its existence controls where log data goes.  "none" turns off
    	   all storage, all log data received will be dropped. Forwarding to
    	   other targets, such as the console, the kernel log buffer, or a
    	   syslog socket will still work however. Defaults to "auto".
    
           Compress=
    	   Takes a boolean value. If enabled (the default), data objects that
    	   shall be stored in the journal and are larger than a certain
    	   threshold are compressed before they are written to the file
    	   system.
    
           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[1] by
    	   G. A. Marson and B. Poettering (doi:10.1007/978-3-642-40203-6_7)
    	   and may be used to protect journal files from unnoticed alteration.
    
           SplitMode=
    	   Controls whether to split up journal files per user. One of "uid",
    	   "login" and "none". If "uid", all users will get each their own
    	   journal files regardless of whether they possess a login session or
    	   not, however system users will log into the system journal. If
    	   "login", actually logged-in users will get each their own journal
    	   files, but users without login session and system users will log
    	   into the system journal. If "none", journal files are not split up
    	   by user and all messages are instead stored in the single system
    	   journal. Note that splitting up journal files by user is only
    	   available for journals stored persistently. If journals are stored
    	   on volatile storage (see above), only a single journal file for all
    	   user IDs is kept. Defaults to "uid".
    
           RateLimitInterval=, RateLimitBurst=
    	   Configures the rate limiting that is applied to all messages
    	   generated on the system. If, in the time interval defined by
    	   RateLimitInterval=, 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 1000 messages in 30s. The time
    	   specification for RateLimitInterval= 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.
    
           SystemMaxUse=, SystemKeepFree=, SystemMaxFileSize=, RuntimeMaxUse=,
           RuntimeKeepFree=, RuntimeMaxFileSize=
    	   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 maximum.  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= is violated when systemd-journald is started, the
    	   value will be raised to 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 go reduce footprint either.
    
    	   SystemMaxFileSize= and RuntimeMaxFileSize= control how large
    	   individual journal files may grow at maximum. 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.
    
           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 then 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 syslog and 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=". When forwarding to the
    	   console, the TTY to log to can be changed with TTYPath=, described
    	   below.
    
           MaxLevelStore=, MaxLevelSyslog=, MaxLevelKMsg=, MaxLevelConsole=,
           MaxLevelWall=
    	   Controls the maximum log level of messages that are stored on disk,
    	   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 written to
    	   disk and forwarded to syslog. Defaults to "notice" for
    	   MaxLevelKMsg=, "info" for MaxLevelConsole=, and "emerg" for
    	   MaxLevelWall=.
    
           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 artifically 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.
    
    FORWARDING TO TRADITIONAL SYSLOG DAEMONS
           Journal events can be transferred to a different logging daemon in two
           different ways. In the first method, messages are immediately forwarded
           to a socket (/run/systemd/journal/syslog), where the traditional syslog
           daemon can read them. This method is controlled by ForwardToSyslog=
           option. In a second method, a syslog daemon behaves like a normal
           journal client, and reads messages from the journal files, similarly to
           journalctl(1). In this method, messages do not have to be read
           immediately, which allows a logging daemon which is only started late
           in boot to access all messages since the start of the system. In
           addition, full structured meta-data is available to it. This method of
           course is available only if the messages are stored in a journal file
           at all. So it will not work if Storage=none is set. It should be noted
           that usually the second method is used by syslog daemons, so the
           Storage= option, and not the ForwardToSyslog= option, is relevant for
           them.
    
    SEE ALSO
           systemd(1), systemd-journald.service(8), journalctl(1),
           systemd.journal-fields(7), systemd-system.conf(5)
    
    NOTES
    	1. Seekable Sequential Key Generators
    	   https://eprint.iacr.org/2013/397
    
    
    
    systemd 219						      JOURNALD.CONF(5)
    

Log in to reply
 

© Lightnetics 2024