X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fjournald.conf.xml;h=95164322f727f8424a221dccb95ca07e4d7625ff;hp=6d54c94b575d022a8991440325561fedb8e564bd;hb=c305c32580a1d7689a401e8cf673ec7936c12bbe;hpb=8621b1109b0bbe097f2b3bfce2211fe8474c567b diff --git a/man/journald.conf.xml b/man/journald.conf.xml index 6d54c94b5..95164322f 100644 --- a/man/journald.conf.xml +++ b/man/journald.conf.xml @@ -54,8 +54,8 @@ Description - This files configures various parameters of the - systemd journal service + This file configures various parameters of the + systemd journal service, systemd-journald.service8. @@ -77,13 +77,13 @@ persistent, auto and none. If - volatile journal + 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 + persistent, data will be stored preferably on disk, i.e. below the /var/log/journal @@ -112,7 +112,7 @@ Compress= Takes a boolean - value. If enabled (the default) data + value. If enabled (the default), data objects that shall be stored in the journal and are larger than a certain threshold are compressed with the XZ @@ -125,14 +125,20 @@ Seal= Takes a boolean - value. If enabled (the default) and a + value. If enabled (the default), and a sealing key is available (as created by journalctl1's - command), forward secure sealing (FSS) for - all persistent journal files is - enabled. + command), Forward Secure Sealing (FSS) + for all persistent journal files is + enabled. FSS is based on Seekable + Sequential Key Generators 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. @@ -143,23 +149,23 @@ of login, uid and none. If - login each logged - in user will get his own journal + login, each logged-in + user will get his own journal files, but systemd user IDs will log into the system journal. If - uid any user ID + uid, any user ID will get his own journal files - regardless whether it belongs to a + regardless of whether it belongs to a system service or refers to a real logged in user. If - none journal files - are not split up per-user and all - messages are stored in the single + 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 per-user is only - available of journals are stored + up journal files by user is only + available for journals stored persistently. If journals are stored - on volatile storage (see above) only a + on volatile storage (see above), only a single journal file for all user IDs is kept. Defaults to login. @@ -171,14 +177,14 @@ Configures the rate limiting that is applied to all - messages generated on the system. If + messages generated on the system. If, in the time interval defined by - RateLimitInterval= + RateLimitInterval=, more messages than specified in RateLimitBurst= are - logged by a service all further + logged by a service, all further messages within the interval are - dropped, until the interval is over. A + dropped until the interval is over. A message about the number of dropped messages is generated. This rate limiting is applied per-service, so @@ -221,34 +227,58 @@ /run/log/journal. The former is used only when /var is mounted, - writable and the directory + writable, and the directory /var/log/journal - exists. Otherwise only the latter + 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, + logging, only the latter options apply, while the former apply if persistent logging is enabled and the system is fully booted - up. SystemMaxUse= + 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. Defaults to 10% of the size - of the respective file - system. SystemKeepFree= - and + journal may use up at maximum. + SystemKeepFree= and RuntimeKeepFree= - control how much disk space the - journal shall always leave free for - other uses if less than the disk space - configured in - SystemMaxUse= and - RuntimeMaxUse= is - available. Defaults to 15% of the size - of the respective file - system. SystemMaxFileSize= + 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. 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 before there was enough + free space and journal files were + created, and subsequently something + else causes the file system to fill + up, journald will stop using more + space, but it'll will not removing + existing files to go reduce footprint + either. + + SystemMaxFileSize= and RuntimeMaxFileSize= control how large individual journal @@ -263,12 +293,13 @@ 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. Note that size limits are - enforced synchronously to journal - files as they are extended, and need - no explicit rotation step triggered by - time. + 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. @@ -276,23 +307,26 @@ The maximum time to store entries in a single journal - file, before rotating to the next - one. Normally time-based rotation + 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 don't grow without + 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 + 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, m to override the - default time unit of + suffixed with the units + year, + month, + week, day, + h or m + to override the default time unit of seconds. @@ -304,31 +338,42 @@ controls whether journal files containing entries older then the specified time span are - deleted. Normally time-based deletion + 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 don't grow without + journal files do not grow without bounds. However, to enforce data - retention policies it might make sense + 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, m + the units year, + month, + week, day, + h or m to override the default time unit of - seconds. + seconds. SyncIntervalSec= - The timeout before syncing journal - data to disk. After syncing journal files have - OFFLINE state. Default timeout is 5 minutes. + 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. @@ -345,8 +390,8 @@ system console. These options take boolean arguments. If forwarding to syslog is enabled but no syslog daemon - is running the respective option has - no effect. By default only forwarding + is running, the respective option has + no effect. By default, only forwarding to syslog is enabled. These settings may be overridden at boot time with the kernel command line options @@ -354,7 +399,10 @@ systemd.journald.forward_to_kmsg= and systemd.journald.forward_to_console=. - + When forwarding to the console, the + TTY to log to can be changed + with TTYPath=, + described below.