[lttng-tools.git] / doc / man / lttng-relayd.8.txt

lttng-relayd(8)
===============
:revdate: 14 June 2021
:daemon-bin-name: lttng-relayd
:daemon-ini-section: relayd


NAME
----
lttng-relayd - LTTng relay daemon


SYNOPSIS
--------
[verse]
*lttng-relayd* [option:--background | option:--daemonize] [option:--config='PATH']
             [option:--control-port='URL'] [option:--data-port='URL'] [option:--fd-pool-size='COUNT']
             [option:--live-port='URL'] [option:--output='DIR'] [option:--group='GROUP']
             [option:--verbose]... [option:--working-directory='DIR']
             [option:--group-output-by-host | option:--group-output-by-session] [option:--disallow-clear]


DESCRIPTION
-----------
include::common-intro.txt[]

An LTTng relay daemon, `lttng-relayd`, is a program which receives trace
data from (possibly remote) LTTng session/consumer daemons and which
writes it to the local file system. The relay daemon also accepts LTTng
live connections from compatible readers (for example,
man:babeltrace2(1)); this is the recommended approach to read trace data
while the remote recording session is active.

By default, a relay daemon listens on all network interfaces to receive
trace data, but only on `localhost` for LTTng live connections. Override
the listening URLs with the option:--control-port, option:--data-port,
and option:--live-port options (see the ``<<url-format,URL format>>''
section below). For example, use the
option:--live-port=+tcp://0.0.0.0:{default_network_viewer_port}+ option
to make a relay daemon listen to LTTng live connections on all network
interfaces.

Once LTTng has completely sent a trace to a relay daemon{nbsp}__RD__,
any LTTng trace reader can read the trace located on the local file
system of{nbsp}__RD__.

By default, `lttng-relayd` doesn't start as a daemon. Make it a daemon
with the option:--daemonize or option:--background option. With those
options, `lttng-relayd` ensures the daemon is listening to incoming
connections before it exits.


include::common-daemon-cfg.txt[]

INI configuration file example:

[source,ini]
----
[relayd]
daemonize=yes
live-port=tcp://0.0.0.0:4567
disallow-clear=yes
----


[[output-directory]]
Output directory
~~~~~~~~~~~~~~~~
The relay daemon uses different output path patterns depending on:

* Its configuration.
+
See the ``<<cfg,Daemon configuration>>'' section above.

* The recording session configuration of the connected peer.
* The LTTng session daemon (see man:lttng-sessiond(8)) version
  of the connected peer.

Consider the following variables:

'BASE'::
    Base output directory: `$LTTNG_HOME/lttng-traces` (`$LTTNG_HOME`
    defaults to `$HOME`) or the argument of the option:--output option.

'HOSTNAME'::
    Hostname of the connected peer.

'SESSION'::
    Recording session name.

'DATETIME'::
    Unique recording session date/time.

'TRACEDIR'::
    Custom trace directory path ('TRACEDIR' part of the argument of the
    nloption:--set-url option of the man:lttng-create(1) command, if
    any).

'SESSIONDV'::
    The version of the LTTng session daemon of the connected peer.

The relay daemon output path patterns are:

With the option:--group-output-by-host option (hostname grouping)::
    Without a custom trace directory:::
+
[verse]
'BASE'/'HOSTNAME'/'SESSION'-'DATETIME'

With a custom trace directory:::
+
[verse]
'BASE'/'HOSTNAME'/'TRACEDIR'

With the option:--group-output-by-session option (recording session grouping)::
    Without a custom trace directory:::
        'SESSIONDV' is at least{nbsp}2.4::::
+
[verse]
'BASE'/'SESSION'/'HOSTNAME'-'DATETIME'

Otherwise::::
    Defaults to the hostname grouping pattern:
+
[verse]
'BASE'/'HOSTNAME'/'SESSION'-'DATETIME'

With a custom trace directory:::
    'SESSIONDV' is at least 2.4::::
+
[verse]
'BASE'/'SESSION'/'HOSTNAME'-'DATETIME'/'TRACEDIR'

Otherwise::::
    Defaults to the hostname grouping pattern:
+
[verse]
'BASE'/'HOSTNAME'/'TRACEDIR'


[[url-format]]
URL format
~~~~~~~~~~
The argument of the option:--control-port='URL',
option:--data-port='URL', and option:--live-port='URL' options is an
URL.

The format of 'URL' is:

[verse]
tcp://('HOST' | 'IPADDR'):__PORT__

with:

('HOST' | 'IPADDR')::
    Binding hostname or IP address.
+
IPv6 address must be enclosed in square brackets (`[` and{nbsp}`]`);
see https://www.ietf.org/rfc/rfc2732.txt[RFC{nbsp}2732].

'PORT'::
    TCP port.


[[options]]
OPTIONS
-------
General daemon configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
option:-b, option:--background::
    Start as a Unix daemon, but keep file descriptors (console) open.
+
With this option, `lttng-relayd` ensures the daemon is listening
to incoming connections before it exits.
+
Use the option:--daemonize option instead to close the file descriptors.

option:-f 'PATH', option:--config='PATH'::
    Configure the daemon using the INI configuration file 'PATH' in
    addition to the default configuration files and the command-line
    options.
+
See the ``<<cfg,Daemon configuration>>'' section above.

option:-d, option:--daemonize::
    Start as a Unix daemon and close file descriptors (console).
+
With this option, `lttng-relayd` ensures the daemon is listening
to incoming connections before it exits.
+
Use the option:--background option instead to keep the file descriptors
open.

option:-x, option:--disallow-clear::
    Disallow clearing operations (see man:lttng-clear(1)).
+
See also the `LTTNG_RELAYD_DISALLOW_CLEAR` environment variable.

option:--fd-pool-size='SIZE'::
    Set the size of the file descriptor pool to 'SIZE' file descriptors.
+
'SIZE' is the maximum number of file descriptors that the relay daemon
may keep open simultaneously.
+
Default: the soft `RLIMIT_NOFILE` resource limit of the process (see
man:getrlimit(2)).

option:-g 'GROUP', option:--group='GROUP'::
    Set the Unix tracing group to 'GROUP' instead of `tracing`.
+
This option is only meaningful when the `root` Unix user starts
`lttng-relayd`.
+
Members of the Unix tracing group may connect to the health check socket
of the relay daemon.
+
See also the `LTTNG_RELAYD_HEALTH` environment variable.

option:-w 'DIR', option:--working-directory='DIR'::
    Set the working directory of the processes the relay daemon creates
    to 'DIR'.
+
See also the `LTTNG_RELAYD_WORKING_DIRECTORY` environment variable.

option:-v, option:--verbose::
    Increase verbosity.
+
Specify this option up to three times to get more levels of verbosity.


Output
~~~~~~
See the ``<<output-directory,Output directory>>'' section above to learn
more.

option:-p, option:--group-output-by-host::
    Group the written trace directories by hostname.
+
As of LTTng{nbsp}{lttng_version}, this is the default output grouping
strategy, but this may change in the future.

option:-s, option:--group-output-by-session::
    Group the written trace directories by recording session name
    instead of by hostname.

option:-o 'DIR', option:--output='DIR'::
    Set the base output directory of the written trace directories to
    'DIR'.


Ports
~~~~~
See the ``<<url-format,URL format>>'' section above to learn more about
the syntax of the 'URL' argument of the following options.

option:-C 'URL', option:--control-port='URL'::
    Listen to control data on URL 'URL'.
+
Default:
+tcp://{default_network_control_bind_address}:{default_network_control_port}+.

option:-D 'URL', option:--data-port='URL'::
    Listen to trace data on URL 'URL'.
+
Default:
+tcp://{default_network_data_bind_address}:{default_network_data_port}+.

option:-L 'URL', option:--live-port='URL'::
    Listen to LTTng live connections on URL 'URL'.
+
Default:
+tcp://{default_network_viewer_bind_address}:{default_network_viewer_port}+.


Program information
~~~~~~~~~~~~~~~~~~~
include::common-help-option.txt[]

option:-V, option:--version::
    Show version and quit.


EXIT STATUS
-----------
*0*::
    Success

*1*::
    Error

*3*::
    Fatal error


ENVIRONMENT
-----------
`LTTNG_ABORT_ON_ERROR`::
    Set to `1` to abort the process after the first error is
    encountered.

`LTTNG_NETWORK_SOCKET_TIMEOUT`::
    Socket connection, receive, and send timeout (milliseconds).
+
Set to `0` or `-1` to set an infinite timeout (default).

`LTTNG_RELAYD_DISALLOW_CLEAR`::
    Set to `1` to disallow clearing operations (see man:lttng-clear(1)).
+
The option:--disallow-clear option overrides this environment variable.

`LTTNG_RELAYD_HEALTH`::
    Path to the health check socket of the relay daemon.

`LTTNG_RELAYD_TCP_KEEP_ALIVE`::
    Set to `1` to enable TCP keep-alive.
+
The TCP keep-alive mechanism allows the detection of dead peers
(man:lttng-sessiond(8)) in cases of unclean termination (for example, a
hard reset) of a peer.
+
Supported on Linux and Solaris only. The default behaviour of the TCP
keep-alive mechanism is OS-specific.
+
Search for `tcp_keepalive` in man:tcp(7) to learn more.

`LTTNG_RELAYD_TCP_KEEP_ALIVE_ABORT_THRESHOLD`::
   The time threshold (seconds) to abort a TCP connection after the
   keep-alive probing mechanism has failed.
+
Set to `0` or `-1` to use the value chosen by the operating system
(default).
+
Supported on Solaris 11 only.
+
Search for `tcp_keepalive_abort_threshold` in man:tcp(7) to learn more.

`LTTNG_RELAYD_TCP_KEEP_ALIVE_IDLE_TIME`::
    Number of seconds a connection needs to be idle before TCP begins
    sending out keep-alive probes.
+
Set to `0` or `-1` to use the value chosen by the operating system
(default).
+
Supported on Linux and Solaris 11 only.
+
On Solaris{nbsp}11, the accepted values are `-1`, `0`, and `10` to
`864000`.
+
Search for `tcp_keepalive_time` and `tcp_keepalive_interval`
in man:tcp(7) on Solaris{nbsp}11 to learn more.

`LTTNG_RELAYD_TCP_KEEP_ALIVE_MAX_PROBE_COUNT`::
    Maximum number of TCP keep-alive probes to send before giving up and
    killing the connection if no response is obtained from the other end.
+
Set to `0` or `-1` to use the value chosen by the operating system
(default).
+
Supported on Linux only.
+
Search for `tcp_keepalive_probes` in man:tcp(7) to learn more.

`LTTNG_RELAYD_TCP_KEEP_ALIVE_PROBE_INTERVAL`::
    Number of seconds between TCP keep-alive probes.
+
Set to `0` or `-1` to use the value chosen by the operating system
(default).
+
Supported on Linux only.
+
Search for `tcp_keepalive_intvl` in man:tcp(7) to learn more.

`LTTNG_RELAYD_WORKING_DIRECTORY`::
    Working directory of the processes the relay daemon creates.
+
The option:--working-directory option overrides this environment
variable.


FILES
-----
`$LTTNG_HOME/.lttng`::
    Unix user's LTTng runtime and configuration directory.

`$LTTNG_HOME/lttng-traces`::
    Default base output directory of LTTng traces.
+
Override this path with the option:--output option.

NOTE: `$LTTNG_HOME` defaults to `$HOME`.


include::common-footer.txt[]


SEE ALSO
--------
man:babeltrace2(1),
man:lttng(1),
man:lttng-sessiond(8)
Commit	Line	Data
	1	lttng-relayd(8)
	2	===============
	3	:revdate: 14 June 2021
	4	:daemon-bin-name: lttng-relayd
	5	:daemon-ini-section: relayd
	6
	7
	8	NAME
	9	----
	10	lttng-relayd - LTTng relay daemon
	11
	12
	13	SYNOPSIS
	14	--------
	15	[verse]
	16	lttng-relayd [option:--background \| option:--daemonize] [option:--config='PATH']
	17	[option:--control-port='URL'] [option:--data-port='URL'] [option:--fd-pool-size='COUNT']
	18	[option:--live-port='URL'] [option:--output='DIR'] [option:--group='GROUP']
	19	[option:--verbose]... [option:--working-directory='DIR']
	20	[option:--group-output-by-host \| option:--group-output-by-session] [option:--disallow-clear]
	21
	22
	23	DESCRIPTION
	24	-----------
	25	include::common-intro.txt[]
	26
	27	An LTTng relay daemon, `lttng-relayd`, is a program which receives trace
	28	data from (possibly remote) LTTng session/consumer daemons and which
	29	writes it to the local file system. The relay daemon also accepts LTTng
	30	live connections from compatible readers (for example,
	31	man:babeltrace2(1)); this is the recommended approach to read trace data
	32	while the remote recording session is active.
	33
	34	By default, a relay daemon listens on all network interfaces to receive
	35	trace data, but only on `localhost` for LTTng live connections. Override
	36	the listening URLs with the option:--control-port, option:--data-port,
	37	and option:--live-port options (see the ``<<url-format,URL format>>''
	38	section below). For example, use the
	39	option:--live-port=+tcp://0.0.0.0:{default_network_viewer_port}+ option
	40	to make a relay daemon listen to LTTng live connections on all network
	41	interfaces.
	42
	43	Once LTTng has completely sent a trace to a relay daemon{nbsp}__RD__,
	44	any LTTng trace reader can read the trace located on the local file
	45	system of{nbsp}__RD__.
	46
	47	By default, `lttng-relayd` doesn't start as a daemon. Make it a daemon
	48	with the option:--daemonize or option:--background option. With those
	49	options, `lttng-relayd` ensures the daemon is listening to incoming
	50	connections before it exits.
	51
	52
	53	include::common-daemon-cfg.txt[]
	54
	55	INI configuration file example:
	56
	57	[source,ini]
	58	----
	59	[relayd]
	60	daemonize=yes
	61	live-port=tcp://0.0.0.0:4567
	62	disallow-clear=yes
	63	----
	64
	65
	66	[[output-directory]]
	67	Output directory
	68	~~~~~~~~~~~~~~~~
	69	The relay daemon uses different output path patterns depending on:
	70
	71	* Its configuration.
	72	+
	73	See the ``<<cfg,Daemon configuration>>'' section above.
	74
	75	* The recording session configuration of the connected peer.
	76	* The LTTng session daemon (see man:lttng-sessiond(8)) version
	77	of the connected peer.
	78
	79	Consider the following variables:
	80
	81	'BASE'::
	82	Base output directory: `$LTTNG_HOME/lttng-traces` (`$LTTNG_HOME`
	83	defaults to `$HOME`) or the argument of the option:--output option.
	84
	85	'HOSTNAME'::
	86	Hostname of the connected peer.
	87
	88	'SESSION'::
	89	Recording session name.
	90
	91	'DATETIME'::
	92	Unique recording session date/time.
	93
	94	'TRACEDIR'::
	95	Custom trace directory path ('TRACEDIR' part of the argument of the
	96	nloption:--set-url option of the man:lttng-create(1) command, if
	97	any).
	98
	99	'SESSIONDV'::
	100	The version of the LTTng session daemon of the connected peer.
	101
	102	The relay daemon output path patterns are:
	103
	104	With the option:--group-output-by-host option (hostname grouping)::
	105	Without a custom trace directory:::
	106	+
	107	[verse]
	108	'BASE'/'HOSTNAME'/'SESSION'-'DATETIME'
	109
	110	With a custom trace directory:::
	111	+
	112	[verse]
	113	'BASE'/'HOSTNAME'/'TRACEDIR'
	114
	115	With the option:--group-output-by-session option (recording session grouping)::
	116	Without a custom trace directory:::
	117	'SESSIONDV' is at least{nbsp}2.4::::
	118	+
	119	[verse]
	120	'BASE'/'SESSION'/'HOSTNAME'-'DATETIME'
	121
	122	Otherwise::::
	123	Defaults to the hostname grouping pattern:
	124	+
	125	[verse]
	126	'BASE'/'HOSTNAME'/'SESSION'-'DATETIME'
	127
	128	With a custom trace directory:::
	129	'SESSIONDV' is at least 2.4::::
	130	+
	131	[verse]
	132	'BASE'/'SESSION'/'HOSTNAME'-'DATETIME'/'TRACEDIR'
	133
	134	Otherwise::::
	135	Defaults to the hostname grouping pattern:
	136	+
	137	[verse]
	138	'BASE'/'HOSTNAME'/'TRACEDIR'
	139
	140
	141	[[url-format]]
	142	URL format
	143	~~~~~~~~~~
	144	The argument of the option:--control-port='URL',
	145	option:--data-port='URL', and option:--live-port='URL' options is an
	146	URL.
	147
	148	The format of 'URL' is:
	149
	150	[verse]
	151	tcp://('HOST' \| 'IPADDR'):__PORT__
	152
	153	with:
	154
	155	('HOST' \| 'IPADDR')::
	156	Binding hostname or IP address.
	157	+
	158	IPv6 address must be enclosed in square brackets (`[` and{nbsp}`]`);
	159	see https://www.ietf.org/rfc/rfc2732.txt[RFC{nbsp}2732].
	160
	161	'PORT'::
	162	TCP port.
	163
	164
	165	[[options]]
	166	OPTIONS
	167	-------
	168	General daemon configuration
	169	~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	170	option:-b, option:--background::
	171	Start as a Unix daemon, but keep file descriptors (console) open.
	172	+
	173	With this option, `lttng-relayd` ensures the daemon is listening
	174	to incoming connections before it exits.
	175	+
	176	Use the option:--daemonize option instead to close the file descriptors.
	177
	178	option:-f 'PATH', option:--config='PATH'::
	179	Configure the daemon using the INI configuration file 'PATH' in
	180	addition to the default configuration files and the command-line
	181	options.
	182	+
	183	See the ``<<cfg,Daemon configuration>>'' section above.
	184
	185	option:-d, option:--daemonize::
	186	Start as a Unix daemon and close file descriptors (console).
	187	+
	188	With this option, `lttng-relayd` ensures the daemon is listening
	189	to incoming connections before it exits.
	190	+
	191	Use the option:--background option instead to keep the file descriptors
	192	open.
	193
	194	option:-x, option:--disallow-clear::
	195	Disallow clearing operations (see man:lttng-clear(1)).
	196	+
	197	See also the `LTTNG_RELAYD_DISALLOW_CLEAR` environment variable.
	198
	199	option:--fd-pool-size='SIZE'::
	200	Set the size of the file descriptor pool to 'SIZE' file descriptors.
	201	+
	202	'SIZE' is the maximum number of file descriptors that the relay daemon
	203	may keep open simultaneously.
	204	+
	205	Default: the soft `RLIMIT_NOFILE` resource limit of the process (see
	206	man:getrlimit(2)).
	207
	208	option:-g 'GROUP', option:--group='GROUP'::
	209	Set the Unix tracing group to 'GROUP' instead of `tracing`.
	210	+
	211	This option is only meaningful when the `root` Unix user starts
	212	`lttng-relayd`.
	213	+
	214	Members of the Unix tracing group may connect to the health check socket
	215	of the relay daemon.
	216	+
	217	See also the `LTTNG_RELAYD_HEALTH` environment variable.
	218
	219	option:-w 'DIR', option:--working-directory='DIR'::
	220	Set the working directory of the processes the relay daemon creates
	221	to 'DIR'.
	222	+
	223	See also the `LTTNG_RELAYD_WORKING_DIRECTORY` environment variable.
	224
	225	option:-v, option:--verbose::
	226	Increase verbosity.
	227	+
	228	Specify this option up to three times to get more levels of verbosity.
	229
	230
	231	Output
	232	~~~~~~
	233	See the ``<<output-directory,Output directory>>'' section above to learn
	234	more.
	235
	236	option:-p, option:--group-output-by-host::
	237	Group the written trace directories by hostname.
	238	+
	239	As of LTTng{nbsp}{lttng_version}, this is the default output grouping
	240	strategy, but this may change in the future.
	241
	242	option:-s, option:--group-output-by-session::
	243	Group the written trace directories by recording session name
	244	instead of by hostname.
	245
	246	option:-o 'DIR', option:--output='DIR'::
	247	Set the base output directory of the written trace directories to
	248	'DIR'.
	249
	250
	251	Ports
	252	~~~~~
	253	See the ``<<url-format,URL format>>'' section above to learn more about
	254	the syntax of the 'URL' argument of the following options.
	255
	256	option:-C 'URL', option:--control-port='URL'::
	257	Listen to control data on URL 'URL'.
	258	+
	259	Default:
	260	+tcp://{default_network_control_bind_address}:{default_network_control_port}+.
	261
	262	option:-D 'URL', option:--data-port='URL'::
	263	Listen to trace data on URL 'URL'.
	264	+
	265	Default:
	266	+tcp://{default_network_data_bind_address}:{default_network_data_port}+.
	267
	268	option:-L 'URL', option:--live-port='URL'::
	269	Listen to LTTng live connections on URL 'URL'.
	270	+
	271	Default:
	272	+tcp://{default_network_viewer_bind_address}:{default_network_viewer_port}+.
	273
	274
	275	Program information
	276	~~~~~~~~~~~~~~~~~~~
	277	include::common-help-option.txt[]
	278
	279	option:-V, option:--version::
	280	Show version and quit.
	281
	282
	283	EXIT STATUS
	284	-----------
	285	0::
	286	Success
	287
	288	1::
	289	Error
	290
	291	3::
	292	Fatal error
	293
	294
	295	ENVIRONMENT
	296	-----------
	297	`LTTNG_ABORT_ON_ERROR`::
	298	Set to `1` to abort the process after the first error is
	299	encountered.
	300
	301	`LTTNG_NETWORK_SOCKET_TIMEOUT`::
	302	Socket connection, receive, and send timeout (milliseconds).
	303	+
	304	Set to `0` or `-1` to set an infinite timeout (default).
	305
	306	`LTTNG_RELAYD_DISALLOW_CLEAR`::
	307	Set to `1` to disallow clearing operations (see man:lttng-clear(1)).
	308	+
	309	The option:--disallow-clear option overrides this environment variable.
	310
	311	`LTTNG_RELAYD_HEALTH`::
	312	Path to the health check socket of the relay daemon.
	313
	314	`LTTNG_RELAYD_TCP_KEEP_ALIVE`::
	315	Set to `1` to enable TCP keep-alive.
	316	+
	317	The TCP keep-alive mechanism allows the detection of dead peers
	318	(man:lttng-sessiond(8)) in cases of unclean termination (for example, a
	319	hard reset) of a peer.
	320	+
	321	Supported on Linux and Solaris only. The default behaviour of the TCP
	322	keep-alive mechanism is OS-specific.
	323	+
	324	Search for `tcp_keepalive` in man:tcp(7) to learn more.
	325
	326	`LTTNG_RELAYD_TCP_KEEP_ALIVE_ABORT_THRESHOLD`::
	327	The time threshold (seconds) to abort a TCP connection after the
	328	keep-alive probing mechanism has failed.
	329	+
	330	Set to `0` or `-1` to use the value chosen by the operating system
	331	(default).
	332	+
	333	Supported on Solaris 11 only.
	334	+
	335	Search for `tcp_keepalive_abort_threshold` in man:tcp(7) to learn more.
	336
	337	`LTTNG_RELAYD_TCP_KEEP_ALIVE_IDLE_TIME`::
	338	Number of seconds a connection needs to be idle before TCP begins
	339	sending out keep-alive probes.
	340	+
	341	Set to `0` or `-1` to use the value chosen by the operating system
	342	(default).
	343	+
	344	Supported on Linux and Solaris 11 only.
	345	+
	346	On Solaris{nbsp}11, the accepted values are `-1`, `0`, and `10` to
	347	`864000`.
	348	+
	349	Search for `tcp_keepalive_time` and `tcp_keepalive_interval`
	350	in man:tcp(7) on Solaris{nbsp}11 to learn more.
	351
	352	`LTTNG_RELAYD_TCP_KEEP_ALIVE_MAX_PROBE_COUNT`::
	353	Maximum number of TCP keep-alive probes to send before giving up and
	354	killing the connection if no response is obtained from the other end.
	355	+
	356	Set to `0` or `-1` to use the value chosen by the operating system
	357	(default).
	358	+
	359	Supported on Linux only.
	360	+
	361	Search for `tcp_keepalive_probes` in man:tcp(7) to learn more.
	362
	363	`LTTNG_RELAYD_TCP_KEEP_ALIVE_PROBE_INTERVAL`::
	364	Number of seconds between TCP keep-alive probes.
	365	+
	366	Set to `0` or `-1` to use the value chosen by the operating system
	367	(default).
	368	+
	369	Supported on Linux only.
	370	+
	371	Search for `tcp_keepalive_intvl` in man:tcp(7) to learn more.
	372
	373	`LTTNG_RELAYD_WORKING_DIRECTORY`::
	374	Working directory of the processes the relay daemon creates.
	375	+
	376	The option:--working-directory option overrides this environment
	377	variable.
	378
	379
	380	FILES
	381	-----
	382	`$LTTNG_HOME/.lttng`::
	383	Unix user's LTTng runtime and configuration directory.
	384
	385	`$LTTNG_HOME/lttng-traces`::
	386	Default base output directory of LTTng traces.
	387	+
	388	Override this path with the option:--output option.
	389
	390	NOTE: `$LTTNG_HOME` defaults to `$HOME`.
	391
	392
	393	include::common-footer.txt[]
	394
	395
	396	SEE ALSO
	397	--------
	398	man:babeltrace2(1),
	399	man:lttng(1),
	400	man:lttng-sessiond(8)