>
> 1 - This example sets the access_log to /dev/null, and the error_log is
>> redirected to stderr which is displayed in the qemu terminal. How can I
>> have access to the access_log ? (you can also view this question in
>> stackoverflow
>> <http://stackoverflow.com/questions/36706926/rump-unikernel-nginx-logs>)
>>
>
> I guess it depends on your use case. For example, you can configure a
> block device with a file system, and log to that. Or, you can configure
> access_log to appear on the console and read it from there.
>
> The usability interface for logging is really more of a question for the
> Orchestrating System (OS) built on top of the Rumprun unikernel.
>
> 2 - Many applications generates information that requires persistence.
>> How
>> could I enable persistence in a rump unikernel ?
>>
>
> I assume that by persistence you mean persistence of data across
> instances. Again, it depends on your use case. For example, you can use
> cloud storage, or a "local" file system (where "local" might mean on the
> cloud -- the cloud is recursively confusing).
>
I am trying to do some things with rump kernels to put my head around how
this technology works. As you said, my current questions might not be with
rump kernels it-self but with the Orchestrating System. I am aware that it
is also possible to send the logs to the console or to a remote syslog, but
I would like to try to store data locally.
I looked at *rumprun-nethack* and I tried to extend "nginx static server"
to log information into /var/log/nginx/access_log. I have not been
completely successful, and I am not sure what I am doing wrong.
1) I created a ext3 filesystem (btw I noticed that nethack is using ext2)
2) modified nginx.conf
#access_log /dev/null;
access_log /var/log/nginx/access_log;
3) rebuilt data.iso
4) Run rumprun qemu adding a new block
rumprun qemu -i -M 128 -I if,vioif,'-net tap,script=no,ifname=tap0' \
-W if,inet,static,10.0.120.101/24 \
-b images/data.iso,/data \
-b log.ext3,/var/log/nginx \
-- ./nginx.bin -c /data/conf/nginx.conf
nginx works, the "access_log" file is created but no information is stored
there.
>
> The remaining issue is how to get the application to sync its data to a
> clean state. Some applications support an "in-band" method for signalling
> a sync, e.g. rumprun-nethack will save the game when the user presses "S".
> For applications which don't support that, normally a signal is used. With
> rump kernels and therefore Rumprun taking heed of the "signals are evil"
> tautology, the signal approach won't work out-of-the-box. Some code
> remains to be conjured up to address the general case.
>
>
I am afraid that I might be facing this problem, but I am not sure about
it. Any help is appreciated!
Regards,
Ruben
