[lttng-dev] Error: opening metadata failed (LTTng on OpenWRT)

[Jérémie Galarneau]

Hi Robin,

Can you add the commands you use to create the session?

Thanks,
Jérémie

On 14 November 2017 at 04:41, Robin Michielsen
<robin.michielsen.1 at gmail.com> wrote:
> Hi all,
>
>
>
> I am trying to trace the Linux kernel (system calls) using LTTng on a
> platform that is running OpenWRT. I have cross compiled the latest versions
> (2.10.x) of the lttng-modules, lttng-tools and lttng-ust packages and
> installed these on my OpenWRT system. Now when I start a kernel trace then
> the lttng tool returns the error "LTTng transport relay-metadata not found /
> Error: Opening metadata failed". Does anybody know what might cause this
> error, or have a hint on what to check?
>
>
>
> I have attached the captured output of ‘lttng-sessiond -vvv
> --verbose-consumer’. Here is some more context:
>
> ·         MIPS platform running Linux 3.18.29
>
> ·         Package versions:
>
> o   lttng-modules-2.10.4
>
> o   lttng-tools-2.10.1
>
> o   lttng-ust-2.10.0
>
> ·         lsmod shows that the following modules have been loaded:
>
> o   lttng_clock
>
> o   lttng_lib_ring_buffer
>
> o   lttng_ring_buffer_client_discard
>
> o   lttng_statedump
>
> o   lttng_tracer
>
> ·         Commands to create and start a session:
>
> o   lttng create
>
> o   lttng enable-event --kernel --syscall open,close
>
> o   lttng start
>
>
>
> When ‘lttng start’ is called then lttng-sessiond’s debug output shows
> “Closing metadata fd -1 (in trace_kernel_destroy_metadata() at
> trace-kernel.c:569)” followed by “Sending response (size: 20, retcode:
> Opening metadata failed (45)) (in thread_manage_clients() at main.c:4641)”.
> I assume that the error that I’m seeing is because for some reason metadata
> fd is being closed.
>
>
>
> Does anybody know what may cause this issue, or have a hint on to check?
>
>
>
> Kind regards,
>
> Robin
>
>
>
>
> _______________________________________________
> lttng-dev mailing list
> lttng-dev at lists.lttng.org
> https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
>



-- 
Jérémie Galarneau
EfficiOS Inc.
http://www.efficios.com