[systemd-devel] systemd-journald.service failed to start with systemd v189

[Nicolas Aguirre]

2012/9/24 Lennart Poettering <lennart at poettering.net>:
> On Mon, 24.09.12 11:43, Nicolas Aguirre (aguirre.nicolas at gmail.com) wrote:
>
>> Hi,
>>
>> Sometimes (around 1% of the time) my system doesn't start correctly.
>> the init process takes 100% CPU. systemd-journal.service is not
>> started correctly, and systemd tries to restart it in a loop.
>> The log is here : http://pastebin.ca/2207127
>>
>> >From my understanding, the problem begins with
>>
>> [   12.169769] systemd[1]: Child 138 died (code=exited, status=1/FAILURE)
>> [   12.169799] systemd[1]: Child 138 belongs to systemd-journald.service
>> [   12.169830] systemd[1]: systemd-journald.service: main process
>> exited, code=exited, status=1
>>
>> I would like to activate journald logs to see if there is debug output
>> for this error. But i have no idea how to activate journal logs.
>>
>> I'm running angstrom and systemd v189 with a linux kernel v3.2.19 on
>> arm cortex a8 CPU.
>>
>> Maybe somebody will have an idea ?
>
> Hmm, most likely there's something in server_init() in journald.c
> failing. Normally, if something fails there it should print a message to
> kmsg about that. But apparently we missued something there... :-(
>
> Could you try to add "log_notice()" messages at various spots in
> server_init() and check if you can spot where the problem is generated?
> you should see the messages in kmsg.
>
> Lennart
>
> --
> Lennart Poettering - Red Hat, Inc.

Ok,

I did what you said, and it appears that the problem is located in
journald.c, in system_journal_open function, when it tries to read the
machine-id,
it can't open /etc/machine-id.

My RFS is readonly , I use Ubi/Ubifs root filesystem. To fix the
problem of machine-id i added a symbolic link :

ln -sf /var/volatile/machine-id /etc/machine-id

IIRC systemd creates this machine-id file once, but in my case it's
created every time i boot because /var/volatile is tmpfs. It seems
that this symbolic link is broken when journald service starts,
sometimes.

To fix my problem, i will create a service which will mount the fs in
rw, create the /etc/machine-id  and remount fs in ro if the machine-id
is not found. It should work in my case because i'm using ubifs, but
how to fix such problem in case of squashfs for example ?

I don't have found the root cause, btw but it's a good start, thanks
for your advises

Regards,
-- 
Nicolas Aguirre
Mail: aguirre.nicolas at gmail.com
Web: http://enna.geexbox.org
Blog: http://dev.enlightenment.fr/~captainigloo/