lttng(1)
========
-:revdate: 16 October 2019
+:revdate: 14 June 2021
NAME
----
-lttng - LTTng 2 tracer control command-line tool
+lttng - Control LTTng tracing
SYNOPSIS
--------
[verse]
-*lttng* [option:--group='GROUP'] [option:--mi=xml] [option:--no-sessiond | option:--sessiond-path='PATH']
- [option:--quiet | option:-verbose...] '<<commands,COMMAND>>' ['COMMAND OPTIONS']
+*lttng* [option:--group='GROUP'] [option:--mi=**xml**] [option:--no-sessiond | option:--sessiond-path='PATH']
+ [option:--relayd-path='PATH'] [option:--quiet | option:-verbose...]
+ '<<commands,COMMAND>>' ['COMMAND OPTIONS']
DESCRIPTION
listening LTTng session daemon (man:lttng-sessiond(8)). A session
daemon:
-* Manages tracing sessions (see man:lttng-create(1) to learn more
- about tracing sessions).
+* Manages recording sessions (see man:lttng-concepts(7) to learn more
+ about recording sessions).
* Controls the various components (like tracers and consumer daemons) of
LTTng.
* Sends asynchronous notifications to user applications.
-By default, the man:lttng-create(1) command automatically spawns a
-session daemon for your Unix user if none is currently running. Override
-the path of the session daemon binary to spawn with the
-option:--sessiond-path option. Avoid automatically spawning a session
-daemon with the option:--no-sessiond option.
+By default, the man:lttng-create(1) command automatically spawns:
+
+* A session daemon for your Unix user if none is currently running.
++
+Override the path of the session daemon binary to spawn with the
+option:--sessiond-path option.
++
+Avoid automatically spawning a session daemon with the
+option:--no-sessiond option.
+
+* A relay daemon (see man:lttng-relayd(8)) if all the following
+ statements are true:
++
+--
+* You specify the nloption:--live option.
+
+* You don't specify any of the nloption:--set-url, nloption:--ctrl-url,
+ or nloption:--data-url options.
+
+* No relay daemon is currently listening for TCP connections on
+ +127.0.0.1:{default_network_viewer_port}+ (default LTTng live reader
+ connection address and port).
+--
++
+Override the path of the relay daemon binary to spawn with the
+option:--relayd-path option.
NOTE: The LTTng project recommends that you start the session daemon at
boot time for stable and long-term tracing.
+See man:lttng-concepts(7) to learn more about the foundational concepts
+of LTTng.
+
+The `lttng` tool offers a subcommand-based command-line interface. The
+``<<commands,COMMANDS>>'' section below lists the available commands.
+
Session daemon connection
~~~~~~~~~~~~~~~~~~~~~~~~~
`tracing`
LTTng-instrumented user applications automatically register to both the
-root session daemon and the user session daemon. This makes it possible
-for both session daemons to list the available traceable applications
-and known instrumentation points (see man:lttng-list(1)).
+root and user session daemons. This makes it possible for both session
+daemons to list the available instrumented applications and their
+instrumentation points (see man:lttng-list(1)).
OPTIONS
+
You may :not: use this option with the option:--no-sessiond option.
+option:--relayd-path='PATH'::
+ Set the absolute path of the relay daemon binary to spawn from the
+ man:lttng-create(1) command to 'PATH'.
+
option:-v, option:--verbose::
Increase verbosity.
+
The following commands also have their own nloption:--help option.
-Tracing session
-~~~~~~~~~~~~~~~
+Recording session
+~~~~~~~~~~~~~~~~~
[options="header"]
|===
|Command |Description
|===
-include::common-cmd-footer.txt[]
+include::common-lttng-cmd-after-options.txt[]
+
+
+include::common-footer.txt[]
SEE ALSO
--------
-man:babeltrace2(1),
+man:lttng-concepts(7)
man:lttng-relayd(8),
man:lttng-sessiond(8)