lttng-save(1) (v2.10)


lttng-save — Save LTTng tracing session configurations


lttng [GENERAL OPTIONS] save [--force] [--output-path=PATH] [SESSION]


The lttng save command saves the configurations of one or more tracing sessions to files.

The lttng save command is used in conjunction with the lttng-load(1) command to save and restore the complete configurations of tracing sessions. This includes the enabled channels and event rules, the context added to channels, the tracing activity, and more. lttng save does not save tracing data, only the tracing session parameters.

If SESSION is omitted, all the existing tracing session configurations are saved (equivalent to using the --all option). Otherwise, SESSION is the name of an existing tracing session. lttng list outputs all the existing tracing sessions (see lttng-list(1)).

The default output directory path is $LTTNG_HOME/.lttng/sessions ($LTTNG_HOME defaults to $HOME). Each tracing session configuration file is named SESSION.lttng, where SESSION is the original tracing session name. The default output directory path can be overridden with the --output-path option.

By default, existing tracing session configuration files are not overwritten when saving; the command fails. The --force option can be used to allow this.


General options are described in lttng(1).

-a, --all

Save all tracing session configurations (default).

-f, --force

Overwrite existing tracing session configuration files when saving.

-o PATH, --output-path=PATH

Set output directory path to PATH.

Program information

-h, --help

Show command help.

This option, like lttng-help(1), attempts to launch /usr/bin/man to view the command’s man page. The path to the man pager can be overridden by the LTTNG_MAN_BIN_PATH environment variable.


List available command options.



Set to 1 to abort the process after the first error is encountered.


Overrides the $HOME environment variable. Useful when the user running the commands has a non-writable home directory.


Absolute path to the man pager to use for viewing help information about LTTng commands (using lttng-help(1) or lttng COMMAND --help).


Path in which the session.xsd session configuration XML schema may be found.


Full session daemon binary path.

The --sessiond-path option has precedence over this environment variable.

Note that the lttng-create(1) command can spawn an LTTng session daemon automatically if none is running. See lttng-sessiond(8) for the environment variables influencing the execution of the session daemon.



User LTTng runtime configuration.

This is where the per-user current tracing session is stored between executions of lttng(1). The current tracing session can be set with lttng-set-session(1). See lttng-create(1) for more information about tracing sessions.


Default output directory of LTTng traces. This can be overridden with the --output option of the lttng-create(1) command.


User LTTng runtime and configuration directory.


Default location of saved user tracing sessions (see lttng-save(1) and lttng-load(1)).


System-wide location of saved tracing sessions (see lttng-save(1) and lttng-load(1)).

Note:$LTTNG_HOME defaults to $HOME when not explicitly set.





Command error


Undefined command


Fatal error


Command warning (something went wrong during the command)


If you encounter any issue or usability problem, please report it on the LTTng bug tracker.



This program is part of the LTTng-tools project.

LTTng-tools is distributed under the GNU General Public License version 2. See the LICENSE file for details.


Special thanks to Michel Dagenais and the DORSAL laboratory at École Polytechnique de Montréal for the LTTng journey.

Also thanks to the Ericsson teams working on tracing which helped us greatly with detailed bug reports and unusual test cases.


LTTng-tools was originally written by Mathieu Desnoyers, Julien Desfossez, and David Goulet. More people have since contributed to it.

LTTng-tools is currently maintained by Jérémie Galarneau.