# journald.conf

## NAME



           journald.conf, journald.conf.d, journald@.conf - Journal service
           configuration files
    


## SYNOPSIS



               /etc/systemd/journald.conf
               /run/systemd/journald.conf
               /usr/local/lib/systemd/journald.conf
               /usr/lib/systemd/journald.conf
               /etc/systemd/journald.conf.d/*.conf
               /run/systemd/journald.conf.d/*.conf
               /usr/local/lib/systemd/journald.conf.d/*.conf
               /usr/lib/systemd/journald.conf.d/*.conf
               /etc/systemd/journald@_NAMESPACE_.conf
               /etc/systemd/journald@_NAMESPACE_.conf.d/*.conf
               /run/systemd/journald@_NAMESPACE_.conf.d/*.conf
               /usr/local/lib/systemd/journald@_NAMESPACE_.conf.d/*.conf
               /usr/lib/systemd/journald@_NAMESPACE_.conf.d/*.conf
    


## DESCRIPTION



           These files configure various parameters of the systemd journal
           service, systemd-journald.service(8). See systemd.syntax(7) for a
           general description of the syntax.
    
           The **systemd-journald** instance managing the default namespace is
           configured by /etc/systemd/journald.conf and associated drop-ins.
           Instances managing other namespaces read
           /etc/systemd/journald@_NAMESPACE_.conf and associated drop-ins with
           the namespace identifier filled in. This allows each namespace to
           carry a distinct configuration. See systemd-journald.service(8)
           for details about journal namespaces.
    


## CONFIGURATION DIRECTORIES AND PRECEDENCE



           The default configuration is set during compilation, so
           configuration is only needed when it is necessary to deviate from
           those defaults. The main configuration file is loaded from one of
           the listed directories in order of priority, only the first file
           found is used: /etc/systemd/, /run/systemd/,
           /usr/local/lib/systemd/ [1], /usr/lib/systemd/. The vendor version
           of the file contains commented out entries showing the defaults as
           a guide to the administrator. Local overrides can also be created
           by creating drop-ins, as described below. The main configuration
           file can also be edited for this purpose (or a copy in /etc/ if it
           is shipped under /usr/), however using drop-ins for local
           configuration is recommended over modifications to the main
           configuration file.
    
           In addition to the main configuration file, drop-in configuration
           snippets are read from /usr/lib/systemd/*.conf.d/,
           /usr/local/lib/systemd/*.conf.d/, and /etc/systemd/*.conf.d/.
           Those drop-ins have higher precedence and override the main
           configuration file. Files in the *.conf.d/ configuration
           subdirectories are sorted by their filename in lexicographic
           order, regardless of in which of the subdirectories they reside.
           When multiple files specify the same option, for options which
           accept just a single value, the entry in the file sorted last
           takes precedence, and for options which accept a list of values,
           entries are collected as they occur in the sorted files.
    
           When packages need to customize the configuration, they can
           install drop-ins under /usr/. Files in /etc/ are reserved for the
           local administrator, who may use this logic to override the
           configuration files installed by vendor packages. Drop-ins have to
           be used to override package drop-ins, since the main configuration
           file has lower precedence. It is recommended to prefix all
           filenames in those subdirectories with a two-digit number and a
           dash, to simplify the ordering. This also defines a concept of
           drop-in priorities to allow OS vendors to ship drop-ins within a
           specific range lower than the range used by users. This should
           lower the risk of package drop-ins overriding accidentally
           drop-ins defined by users. It is recommended to use the range
           10-40 for drop-ins in /usr/ and the range 60-90 for drop-ins in
           /etc/ and /run/, to make sure that local and transient drop-ins
           take priority over drop-ins shipped by the OS vendor.
    
           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" 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.
    
               When journal namespacing (see _LogNamespace=_ in
               systemd.exec(5)) is used, setting _Storage=_ to "volatile" or
               "auto" will not have an effect on the creation of the
               per-namespace logs directory in /var/log/journal/, as the
               systemd-journald@.service service file by default carries
               _LogsDirectory=_. To turn that off, add a unit file drop-in file
               that sets _LogsDirectory=_ to an empty string.
    
               Note that per-user journal files are not supported unless
               persistent storage is enabled, thus making **journalctl --user**
               unavailable.
    
               The storage to use can also be specified via the
               "journal.storage" credential. Values configured via
               configuration files take priority over values configured via
               the credential.
    
               Added in version 186.
    
           _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******[2] 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.
    
               Added in version 189._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******[3] for more details
               about UID ranges. If "none", journal files are not split up by
               user and all messages are instead stored in the single system
               journal. In this mode unprivileged users generally do not have
               access to their own log data. Note that splitting up journal
               files by user is only available for journals stored
               persistently. If journals are stored on volatile storage (see _Storage=_ above), only a single journal file is used. Defaults
               to "uid".
    
               Added in version 190.
    
           _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 of the calculated
               default values 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=_ capped to 128M, so that usually seven rotated
               journal files are kept as history. If the journal compact mode
               is enabled (enabled by default), the maximum file size is
               capped to 4G.
    
               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.
    
               Added in version 195.
    
           _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.
    
               Added in version 195.
    
           _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.
    
               Added in version 199.
    
           _ForwardToSyslog=_ , _ForwardToKMsg=_ , _ForwardToConsole=_ ,
           _ForwardToWall=_ , _ForwardToSocket=_
               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, sent as wall
               messages to all logged-in users or sent over a socket. These
               options take boolean arguments except for "ForwardToSocket="
               which takes an address instead. 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.
    
               The socket forwarding address can be specified with the
               credential "journal.forward_to_socket". The following socket
               types are supported:
    
               **AF_INET**(e.g. "192.168.0.11:4444"), **AF_INET6**(e.g.
               "[2001:db8::ff00:42:8329]:4444"), **AF_UNIX**(e.g.
               "/run/host/journal/socket"), **AF_VSOCK**(e.g. "vsock:2:1234")
    
               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").
    
               When forwarding over a socket the **Journal Export Format******[4] is
               used when sending over the wire. Notably this includes the
               metadata field ___REALTIME_TIMESTAMP_ so that
               **systemd-journal-remote**(see systemd-journal-remote.service(8))
               can be used to receive the forwarded journal entries.
    
               Note: Forwarding is performed synchronously within journald,
               and may significantly affect its performance. This is
               particularly relevant when using ForwardToConsole=yes in cloud
               environments, where the console is often a slow, virtual
               serial port. Since journald is implemented as a conventional
               single-process daemon, forwarding to a completely hung console
               will block journald. This can have a cascading effect
               resulting in any services synchronously logging to the blocked
               journal also becoming blocked. Unless actively
               debugging/developing something, it is generally preferable to
               setup a **journalctl --follow** style service redirected to the
               console, instead of ForwardToConsole=yes, for production use.
    
               Note: Using _ForwardToSocket=_ over IPv4/IPv6 links can be very
               slow due to the synchronous nature of the sockets. Take care
               to ensure your link is a low-latency local link if possible.
               Typically IP networking is not available everywhere journald
               runs, e.g. in the initrd during boot. Consider using
               **AF_VSOCK** /**AF_UNIX** sockets for this if possible.
    
           _MaxLevelStore=_ , _MaxLevelSyslog=_ , _MaxLevelKMsg=_ , _MaxLevelConsole=_ ,
           _MaxLevelWall=_ , _MaxLevelSocket=_
               Controls the maximum log level of messages that are stored in
               the journal, forwarded to syslog, kmsg, the console, the wall,
               or a socket (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=_ ,
               _MaxLevelSyslog=_ and _MaxLevelSocket=_ , to ensure that the all
               messages are stored in the journal, forwarded to syslog and
               the socket if one exists. 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=",
               "systemd.journald.max_level_socket=".
    
               Added in version 185.
    
           _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.
    
               Added in version 235.
    
           _Audit=_
               Takes a boolean value. If enabled **systemd-journald** 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. 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 in the
               default journal namespace, and unset otherwise.
    
               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. If you
               need to prevent **systemd-journald** from collecting the generated
               messages, the socket unit "systemd-journald-audit.socket" can
               be disabled and, in this case, this setting is without effect.
    
               Added in version 246.
    
           _TTYPath=_
               Change the console TTY to use if _ForwardToConsole=yes_ is used.
               Defaults to /dev/console.
    
               Added in version 185.
    
           _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.
    
               Added in version 235.
    


## FORWARDING TO TRADITIONAL SYSLOG DAEMONS



           Journal events can be transferred to a different logging daemon in
           two different ways. With 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 the _ForwardToSyslog=_ option. With a second method, a
           syslog daemon behaves like a normal journal client, and reads
           messages from the journal files, similarly to journalctl(1). With
           this, 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.
    


## NOTES



            1. 💣💥🧨💥💥💣 Please note that those configuration files must
               be available at all times. If /usr/local/ is a separate
               partition, it may not be available during early boot, and must
               not be used for configuration.
    
            2. Seekable Sequential Key Generators
               https://eprint.iacr.org/2013/397
    
            3. Users, Groups, UIDs and GIDs on systemd systems
               https://systemd.io/UIDS-GIDS
    
            4. Journal Export Format
               https://systemd.io/JOURNAL_EXPORT_FORMATS/#journal-export-format
    


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