[lttng-dev] Error: Unable to list kernel events: Kernel tracer not available

Fri Nov 30 18:22:05 EST 2018

Hello,

I'm new to lttng so I tried to follow the 'Quick Start' tutorial from
lttng.org.

I have installed LTTng Stable 2.10 PPA (lttng-tools, lttng-modules-dkms,
liblttng-ust-dev). At very beginning I am facing a problem with kernel
tracking:

~/lttng_train$ sudo lttng create my
Session my created.
Traces will be written in /home/szymon/lttng-traces/my-20181130-222008
~/lttng_train$ sudo lttng list --kernel
Error: Unable to list kernel events: Kernel tracer not available
Error: Command error

Any ideas? Thanks for support!

Additional info:

~/lttng_train$ dpkg -l | grep lttng
 ii  liblttng-ctl0:amd64
2.10.5-1~ubuntu16.04.1                       amd64        LTTng
control and utility library
 ii  liblttng-ust-ctl4:amd64
2.10.2-1~ubuntu16.04.1                       amd64        LTTng 2.0
Userspace Tracer (trace control library)
 ii  liblttng-ust-dev:amd64
2.10.2-1~ubuntu16.04.1                       amd64        LTTng 2.0
Userspace Tracer (development files)
 ii  liblttng-ust-python-agent0:amd64
2.10.2-1~ubuntu16.04.1                       amd64        LTTng 2.0
Userspace Tracer (Python agent native library)
 ii  liblttng-ust0:amd64
2.10.2-1~ubuntu16.04.1                       amd64        LTTng 2.0
Userspace Tracer (tracing libraries)
 ii  lttng-modules-dkms
2.10.8-1~ubuntu16.04.1                       all          Linux Trace
Toolkit (LTTng) kernel modules (DKMS)
 ii  lttng-tools
2.10.5-1~ubuntu16.04.1                       amd64        LTTng
control and utility programs

~$ uname -a
Linux szymon 4.4.0-98-generic #121-Ubuntu SMP Tue Oct 10 14:24:03 UTC
2017 x86_64 x86_64 x86_64 GNU/Linux

~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 16.04.5 LTS
Release:    16.04
Codename:   xenial

~/lttng_train$ ps aux | grep lttng-sessiond
root      7862  0.0  0.3 859960 10880 ?        Ssl  19:12   0:00
/usr/bin/lttng-sessiond
szymon   14853  0.0  0.0  15440   936 pts/1    S+   22:21   0:00 grep
--color=auto lttng-sessiond

~/lttng_train$ lsmod | grep lttng
~/

~/lttng_train$ sudo lttng-sessiond -vvv
DEBUG1 - 00:16:41.328643679 [16578/16578]: [sessiond configuration]
DEBUG1 - 00:16:41.328715142 [16578/16578]: 	verbose:                       3
DEBUG1 - 00:16:41.328723618 [16578/16578]: 	verbose consumer:              0
DEBUG1 - 00:16:41.328729230 [16578/16578]: 	quiet mode:                    False
DEBUG1 - 00:16:41.328735428 [16578/16578]: 	agent_tcp_port:
    [5345, 5354]
DEBUG1 - 00:16:41.328741084 [16578/16578]: 	application socket timeout:    5
DEBUG1 - 00:16:41.328761096 [16578/16578]: 	no-kernel:                     False
DEBUG1 - 00:16:41.328776829 [16578/16578]: 	background:                    False
DEBUG1 - 00:16:41.328788328 [16578/16578]: 	daemonize:                     False
DEBUG1 - 00:16:41.328800092 [16578/16578]: 	signal parent on start:        False
DEBUG1 - 00:16:41.328812153 [16578/16578]: 	tracing group name:
    tracing
DEBUG1 - 00:16:41.328823395 [16578/16578]: 	kmod_probe_list:               None
DEBUG1 - 00:16:41.328834022 [16578/16578]: 	kmod_extra_probe_list:         None
DEBUG1 - 00:16:41.328848328 [16578/16578]: 	rundir:
    /var/run/lttng
DEBUG1 - 00:16:41.328857048 [16578/16578]: 	application socket path:
    /var/run/lttng/lttng-ust-sock-7
DEBUG1 - 00:16:41.328866302 [16578/16578]: 	client socket path:
    /var/run/lttng/client-lttng-sessiond
DEBUG1 - 00:16:41.328881494 [16578/16578]: 	wait shm path:
    /lttng-ust-wait-7
DEBUG1 - 00:16:41.328890337 [16578/16578]: 	health socket path:
    /var/run/lttng/sessiond-health
DEBUG1 - 00:16:41.328896087 [16578/16578]: 	LTTNG_UST_CLOCK_PLUGIN:        None
DEBUG1 - 00:16:41.328902562 [16578/16578]: 	pid file path:
    /var/run/lttng/lttng-sessiond.pid
DEBUG1 - 00:16:41.328909781 [16578/16578]: 	lock file path:
    /var/run/lttng/lttng-sessiond.lck
DEBUG1 - 00:16:41.328916938 [16578/16578]: 	session load path:             None
DEBUG1 - 00:16:41.328924592 [16578/16578]: 	agent port file path:
    /var/run/lttng/agent.port
DEBUG1 - 00:16:41.328936395 [16578/16578]: 	consumerd32 path:
    /var/run/lttng/ustconsumerd32
DEBUG1 - 00:16:41.328947517 [16578/16578]: 	consumerd32 bin path:
    Unknown
DEBUG1 - 00:16:41.328961683 [16578/16578]: 	consumerd32 lib dir:
    Unknown
DEBUG1 - 00:16:41.328970009 [16578/16578]: 	consumerd32 err unix sock
path:/var/run/lttng/ustconsumerd32/error
DEBUG1 - 00:16:41.328977730 [16578/16578]: 	consumerd32 cmd unix sock
path:/var/run/lttng/ustconsumerd32/command
DEBUG1 - 00:16:41.328985023 [16578/16578]: 	consumerd64 path:
    /var/run/lttng/ustconsumerd64
DEBUG1 - 00:16:41.328992714 [16578/16578]: 	consumerd64 bin path:
    /usr/lib/x86_64-linux-gnu/lttng/libexec/lttng-consumerd
DEBUG1 - 00:16:41.329005793 [16578/16578]: 	consumerd64 lib dir:
    /usr/lib/x86_64-linux-gnu
DEBUG1 - 00:16:41.329017089 [16578/16578]: 	consumerd64 err unix sock
path:/var/run/lttng/ustconsumerd64/error
DEBUG1 - 00:16:41.329028919 [16578/16578]: 	consumerd64 cmd unix sock
path:/var/run/lttng/ustconsumerd64/command
DEBUG1 - 00:16:41.329040967 [16578/16578]: 	kconsumerd path:
    /var/run/lttng/kconsumerd
DEBUG1 - 00:16:41.329053218 [16578/16578]: 	kconsumerd err unix sock
path: /var/run/lttng/kconsumerd/error
DEBUG1 - 00:16:41.329064330 [16578/16578]: 	kconsumerd cmd unix sock
path: /var/run/lttng/kconsumerd/command
DEBUG3 - 00:16:41.329076040 [16578/16578]: Creating LTTng run
directory: /var/run/lttng (in create_lttng_rundir() at main.c:5306)
Error: A session daemon is already running.
DEBUG1 - 00:16:41.329161207 [16578/16578]: Cleaning up options (in
sessiond_cleanup_options() at main.c:648)
DEBUG1 - 00:16:41.329178082 [16578/16578]: Destroying run_as worker
(in run_as_destroy_worker() at runas.c:709)

Regards,

Simon
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.lttng.org/pipermail/lttng-dev/attachments/20181201/51664d4b/attachment-0001.html>