[lttng-dev] Probleme with live session on LTTng 2.7.0

[Jonathan Rajotte-Julien]

Hi Thierry,

Babeltrace v1.5.5 is the latest stable version available for Babeltrace. Hence you are good on that end.

LTTng 2.7 is NOT the latest stable available. Since you now have the lttng ppa configured, please upgrade all lttng (lttng-tools lttng-modules-dkms) related packages on both the target and the lttng-relayd host (192.168.0.1).

> Questions :
> - how to change (none) into an other name ?

Not sure how you got the "(none)" there in the first place, make sure that your target have a valid hostname. Note that lttng uses "gethostname" to retrieve the hostname of your machine. 
Please try "hostname" in a shell on your target and report your finding.

Still you are making progress since you are able to list the available live session.

> - on the target, I have "Warning : No tracing group detected", how to remove this warning ?

Well all info is in the warning. If you plan on only doing tracing under the root user you can ignore this warning. Otherwise you can create a linux group called "tracing".

Please read [1] for further information about the tracing group.

[1] https://lttng.org/docs/v2.10/#doc-tracing-group

Hope this helps

Cheers


----- Original Message -----
> From: "BADEUIL Thierry" <thierry.badeuil at thalesgroup.com>
> To: "Jonathan Rajotte-Julien" <jonathan.rajotte-julien at efficios.com>
> Cc: "lttng-dev" <lttng-dev at lists.lttng.org>
> Sent: Tuesday, June 12, 2018 6:53:16 AM
> Subject: RE: [lttng-dev] Probleme with live session on LTTng 2.7.0

> And last answer, here is the exact error message :
> tmxv3 at tmxv3-ThinkPad-T530:~$ sudo babeltrace -i lttng-live
> net://localhost/host/\(none\)/test -v
> [verbose] Verbose mode active.
> [verbose] Converting from directory(ies):
> [verbose]     net://localhost/host/(none)/test
> [verbose] Converting from format: lttng-live
> [verbose] Converting to target: <stdout>
> [verbose] Converting to format: text <default>
> [error] Format : net://<hostname>/host/<traced_hostname>/<session_name>
> [warning] [Context] Cannot open_trace of format lttng-live at path
> net://localhost/host/(none)/test.
> [warning] [Context] cannot open trace "net://localhost/host/(none)/test" for
> reading.
> [error] opening trace "net://localhost/host/(none)/test" for reading.
> 
> [error] none of the specified trace paths could be opened.
> 
> So ?
> 
> Thierry BADEUIL
> THALES COMMUNICATIONS
> T : +33 1 46 133 591
> (  : +33 6 85 51 28 16
>  : thierry.badeuil at thalesgroup.com
> 
> 
> -----Message d'origine-----
> De : Jonathan Rajotte-Julien [mailto:jonathan.rajotte-julien at efficios.com]
> Envoyé : lundi 11 juin 2018 19:26
> À : BADEUIL Thierry
> Cc : lttng-dev
> Objet : Re: [lttng-dev] Probleme with live session on LTTng 2.7.0
> 
> Hi,
> 
> ----- Original Message -----
>> From: "BADEUIL Thierry" <thierry.badeuil at thalesgroup.com>
>> To: "Jonathan Rajotte-Julien" <jonathan.rajotte-julien at efficios.com>
>> Cc: "lttng-dev" <lttng-dev at lists.lttng.org>
>> Sent: Monday, June 11, 2018 1:09:58 PM
>> Subject: RE: [lttng-dev] Probleme with live session on LTTng 2.7.0
> 
>> Hello,
>> 
>> Everything is almost OK except when I tried : babeltrace -i lttng-live
>> net://localhost/host/<your hostname>/<session-name>
> 
> Please give us the output of the following when everything else is setup:
> 
> babeltrace -i lttng-live net://localhost
> 
>> 
>> Error messages :
>> - [error] Format : net://....
>> - [warning] [Context] Cannot open_trace of format lttng-live at path...
>> - [warning] [Context] Cannot open trace "..." for reading
>> - [error] opening trace "..."
>> - [error] none of the specified trace paths could be opened.
> 
> Base on this output you seem to be "opening" the "net://..." path? Not sure why.
> 
>> 
>> Do you know why ?
>> 
>> I updated babeltrace to 1.5.5 version and I installed 2.7 LTTng.
> 
> Perfect regarding Babeltrace but I would recommend that you upgrade lttng to the
> latest stable (2.10).
> 
>> 
>> Regards