[libvirt] Seeking for advice on 'virsh console' problems debugging

[Daniel P. Berrange]

On Fri, Mar 07, 2014 at 07:49:04PM +0400, Roman Bogorodskiy wrote:
>   Daniel P. Berrange wrote:
> 
> > On Fri, Mar 07, 2014 at 06:15:24PM +0400, Roman Bogorodskiy wrote:
> > >   Daniel P. Berrange wrote:
> > > 
> > > > All those mangled messages are being printed out by libvirt client
> > > > code, and it is totally expected that log messages libvirt prints
> > > > are mangled in this way for the console.
> > > > 
> > > > What's more important is what data coming from the guest looks
> > > > like.
> > > 
> > > All those spaces come from the stream as well. For example, I've added
> > > the following debugging to daemonStreamHandleRead() into
> > > daemon/stream.c:
> > > 
> > > 732     ret = virStreamRecv(stream->st, buffer, bufferLen);
> > > 733     VIR_ERROR("buffer = [%s]", buffer);
> > > 
> > > And it prints stuff like:
> > > 
> > > 2014-03-07 13:29:34.060+0000: 34489787392: error :
> > > daemonStreamHandleRead:733 : buffer = [  File "/usr/bin/cloud    raise
> > > DataSourceNotFoundException(msg)
> > > ]
> > > 2014-03-07 13:29:34.060+0000: 34489787392: error :
> > > daemonStreamHandleRead:733 : buffer = [
> > > ]
> > > 2014-03-07 13:29:34.061+0000: 34489787392: error :
> > > daemonStreamHandleRead:733 : buffer = [
> > > ]
> > > 2014-03-07 13:29:34.061+0000: 34489787392: error :
> > > daemonStreamHandleRead:733 : buffer = [
> > > ]
> > 
> > The debug logs are *always* going to be strange when you have the
> > terminal in raw mode. If you're debugging the console support you
> > really must not try to use stderr for debug logs - you'll never get
> > sane results. Set libvirt to log to a file or syslog instead.
> 
> That's strange because libvirtd and virsh use different terminals for
> logging, but I've disabled stderr logging to be on the safe side.
> 
> Anyway, I've conducted an experiment like you suggested:
> 
> 1. run 'virsh' on linux to freebsd libvirtd, output is mangled:
> 
>  http://people.freebsd.org/~novel/misc/ttyweirdness2.png
> 
>  2. run 'virsh' on freebsd to linux libvirtd, output is good:
> 
>  http://people.freebsd.org/~novel/misc/ttyweirdness3.png
> 
> Guest uses the same image and the same domain xml.
> 
> Also, I removed all my custom debug stuff from virsh except mutex lock
> (as it doesn't work otherwise). So the problem seem to be on the
> libvirtd side...

Agreed, it is either libvirtd or bhyve that's the source of the
mangling then.

Regards,
Daniel
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