-r --reverse Reverse so newest entries are displayed first.
| --no-full
--full
-l
Ellipsize fields when they do not fit. The default is to show full fields, allowing them to wrap or be
truncated by the pager
| -a
--all Show all fields in full
| -f --follow Do not exit, rather display new entries as they are appended .
Implies --lines=10
| -n --lines=nn|all Show the most recent events and limit the number of events .
all disables line limiting. The default value is 10
| -e --pager-end Start at the end inside the pager, implies -n1000 so the pager
will not buffer logs of unbounded size. may be overridden with -n ,
-nall disables this cap. only for less
| --no-tail Show all stored output lines, even in follow mode. Undoes the effect of --lines= .
| -o --output=
Controls the formatting of the entries that are shown. Takes one of the following options:
short default generates output similar to classic syslog
| cat very terse output, showing the actual message of with no metadata,
| short-full
shows timestamps as --since= and --until= options accepted
include weekday, year and timezon e information in the output, and is locale-independent.
| short-iso shows (ISO 8601) T[hh][mm][ss] timestamps.
| short-precise shows timestamps with microseconds.
| short-monotonic shows monotonic timestamps
| short-unix shows seconds since epoch.
verbose shows the full-structured entry items with all fields.
| export
serializes the journal into a binary (but mostly text-based) stream suitable for backups and network transfer (see
Journal Export Format[1]
| json formats entries as JSON data structures, one per line (see Journal JSON Format[2]
| json-pretty formats entries as JSON more readable by humans.
| json-sse formats entries as JSON data structures, wraps in a format suitable for Server-Sent Events[3].
| | | | | | | | | | | | | |
| --utc time UTC
| --no-hostname
Don't show the hostname field from the local host. only effect on the short form of output
| -x --catalog Augment log lines with explanation texts
explain the context of an error or log event, possible
solutions, as well as pointers to support forums, developer documentation, and any other relevant manuals.
help is not available for all messages. Refer to the Message Catalog Developer Documentation[4].
| -q --quiet
Suppresses info messages (i.e. "-- Logs begin at ...", "-- Reboot --"), warnings regarding inaccessible
system journals when run as a normal user.
| -m --merge Show entries interleaved from all available journals, including remote ones.
| --list-boots Show a list of boot numbers (relative to the current boot), IDs, and timestamps of the first and last message pertaining to the boot.
Example:
0 76727533a534499ebfe90a1f6c9eca7c Tue 2019-07-23 15:50:01 EDT<80><94>Sat 2019-07-27 21:30:01 EDT
| -b --boot=[ID][+-offset]
Show messages from a specific boot. add a match for "_BOOT_ID= ".
With no argument logs since the current boot will be shown.
If the boot ID is omitted, a positive offset refers to boots starting from the beginning of the journal.
ID ≤ 0 offset will look up boots starting from the end of the journal.
1 refers to the first boot 2 the second; -0 is the last boot, -1 the boot before last, and so on.
An empty offset is equivalent to -0 , except when the current boot is not the last boot (e.g. --directory was
specified to look at logs from a different machine).
If the 32-character ID is specified, it may be followed by offset which identifies the boot relative to the one
given by boot ID. Negative values mean earlier boots and positive values mean later boots.
If offset is not specified, a value of zero is assumed, and the logs for the boot given by ID are shown.
|
-k --dmesg Show only kernel messages. implies --boot and adds match "_TRANSPORT=kernel" .
| -t --identifier=syslog_identifier Show messages for the specified syslog identifier SYSLOG_IDENTIFIER.
May be specified multiple times.
| -u --unit=unit|pattern
Show messages for the specified systemd unit UNIT (such as a service unit), or for any of the units matched by PATTERN. If a
pattern is specified, a list of unit names found in the journal is compared with the specified pattern and all that match are
used. For each unit name, a match is added for messages from the unit ("_SYSTEMD_UNIT=UNIT"), along with additional matches
for messages from systemd and messages about coredumps for the specified unit.
May be specified multiple times.
| --user-unit=
Show messages for the specified user session unit. This will add a match for messages from the unit ("_SYSTEMD_USER_UNIT="
and "_UID=") and additional matches for messages from session systemd and messages about coredumps for the specified unit.
May be specified multiple times.
|
-p --priority=n| emerg | alert | crit | err | warning | notice | debug
Filter output by priorities or ranges.
If a single level is specified, all messages with this level or a lower (more important) level are shown.
If a range is specified, messages with this level within the range, inclusive are shown.
Adds PRIORITY= "
| -c --cursor=location show entries from the location
--show-cursor The cursor is shown after the last entry after two dashes: example:
--cursor: s=0639…
| --after-cursor= Show entries from the location after the location specified by the passed cursor.
| -S --since=ccyy-mm-dd [hh:mm:ss]
-U
--until= …
Start examining entries "on or newer then" or "on or older then"
ccyy-mm-dd[ 
hh:mm defaults to 00:00 and :ss :00 .
Date defaults to the current day.
yesterday, today, tomorrow?? are allowed, which refer to 00:00:00 of the day before the current day, the
current day, or the day after the current day. now refers to the current time.
Finally, relative times may be specified, prefixed with "-" or "+", referring to times before or after the current time.
For time and date specification, see systemd.time(7).
--output=short-full displays timestamps that follow this format.
| -F --field=f output all possible data values the field can take in all entries of the journal.
| -N --fields output all field names currently used in all entries (43 )
|
PRIORITY
JOURNAL_NAME
JOURNAL_PATH
USER_ID
SYSLOG_FACILITY
CODE_FILE
MESSAGE
UNIT
USER_UNIT
CODE_LINE
RESULT
LEADER
USERSPACE_USEC
_SYSTEMD_SLICE
_SYSTEMD_CGROUP
_SYSTEMD_SESSION
_SYSTEMD_USER_UNIT
_SYSTEMD_INVOCATION_ID
_SYSTEMD_USER_SLICE
_SYSTEMD_UNIT
_SYSTEMD_OWNER_UID
MESSAGE_ID
CODE_FUNCTION
SESSION_ID
SYSLOG_PID
SYSLOG_IDENTIFIER
_EXE
_SOURCE_REALTIME_TIMESTAMP
_CAP_EFFECTIVE
_CMDLINE
_TRANSPORT
_COMM
_HOSTNAME
_GID
_PID
_MACHINE_ID
_UID
_BOOT_ID
_SOURCE_MONOTONIC_TIMESTAMP
LIMIT[_PRETTY]
MAX_USE[_PRETTY]
CURRENT_USE[_PRETTY]
AVAILABLE[_PRETTY]
DISK_AVAILABLE[_PRETTY]
DISK_KEEP_FREE[_PRETTY]
| | | | |
| --system Show messages from system services and the kernel
| --userShow messages from services of current user (default)
| -M --machine=container Show messages from a running, local container.
| -D dir --directory=dir
operate on a journal directory DIR instead of
the default runtime and system journal paths.
| --file=glob operate on the journal files matching GLOB …
May be specified multiple times, in which case files will be interleaved.
| --root=root
operate on journal directories and catalog file
hierarchy below root instead of the root directory (e.g. --update-catalog will create
ROOT/var/lib/systemd/catalog/database, and journal files under ROOT/run/journal or ROOT/var/log/journal will be displayed).
| --new-id128 Generate a unique 128-bit ID for identifying messages.
| --header show internal header information of the journal fields accessed.
| --disk-usage Shows disk usage of all journal files including archived and active journal files.
Archived and active journals take up 21.6M
--vacuum-size= --vacuum-time= --vacuum-files=
Removes journal files until the disk space they use is below the size ("K",
"M", "G" and "T" suffixes), or
all archived journal files contain no data older than the specified timespan (specified with
the usual "s", "m", "h", "days", "months", "weeks" and "years" suffixes), or
no more than the specified number of separate journal files remain.
running --vacuum-size= has only an indirect effect on the output shown by --disk-usage, as
the latter includes active journal files, while the vacuuming operation only operates on archived journal files. Similarly,
Does not remove active journal files.
--vacuum-size=-,-vacuum-time= and --vacuum-files= may be combined
zero is equivalent to not enforcing the specific limit, and is thus redundant.
| --list-catalog [128-bit-ID …]
List the contents of the message catalog as a table of message IDs, plus their short description strings.
If any 128-bit-IDs are specified, only those entries are shown.
| --dump-catalog [128-bit-ID...]
Show the contents of the message catalog, with entries separated by a line consisting of two dashes and the ID (the format is
the same as .catalog files).
If any 128-bit-IDs are specified, only those entries are shown.
| --update-catalog
Update the message catalog index. This command needs to be executed each time new catalog files are installed, removed, or
updated to rebuild the binary catalog index.
| --setup-keys
Instead of showing journal contents, generate a new key pair for Forward Secure Sealing (FSS). This will generate a sealing
key and a verification key. The sealing key is stored in the journal data directory and shall remain on the host. The
verification key should be stored externally. Refer to the Seal= option in journald.conf(5) for information on Forward Secure
Sealing and for a link to a refereed scholarly paper detailing the cryptographic theory it is based on.
| --force
When --setup-keys is passed and Forward Secure Sealing (FSS) has already been configured, recreate FSS keys.
| --interval=
Specifies the change interval for the sealing key when generating an FSS key pair with --setup-keys. Shorter intervals
increase CPU consumption but shorten the time range of undetectable journal alterations. Defaults to 15min.
| --verify
Check the journal file for internal consistency. If the file has been generated with FSS enabled and the FSS verification key
has been specified with --verify-key=, authenticity of the journal file is verified.
| --verify-key=
Specifies the FSS verification key to use for the --verify operation.
| --sync
Instructs journald to write all data to files and synchronize all journals.
Does not return until the synchronization is complete.
| --flush
daemon flushes data stored in /run/log/journal to /var/log/journal,
if persistent storage is enabled.
Does not return until complete.
Idempotent: i.e. the data is flushed once during system runtime, and this command exits cleanly without
executing any operation if this has already happened.
--rotate Instructs journald to rotate journal files.
Does not return until the rotation is complete.
| --no-pager Do not pipe output into a pager.
| -h --help Print a short help text and exit.
| --version Print a short version string and exit.
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