[libvirt-users] redirecting guest stdio to the host

[Alexander Binun]

Dear Friends, 
  I would ask you a question ; grateful in advance!

I have a program running on a VM guest. Its output is valuable (for VM introspection) so I want to let the host module know about it. I prefer to redirect  ' stdio" of a guest into a device at the host (a text file or my device that has the name "mydev" 
and the driver is written for it). 

I have the XML definition file for my VM in /etc/libvirt/qemu. I have added the section:

    <serial type="file">
      <source path="/var/log/vm/vml.log"/>
      <target port="0"/>
    </serial>
  
into the /devices section.

That is I want the stdio to be streamed into the file /var/log/vm/vml.log at the host.

Then I run simple textual commands at the guest (ls, pwd and so on). But I do not see /var/log/vm/vml.log created at the host.

Please help me.

Thanks in advance,
   Alexander Binun


> 
> The command string for qemu will look like qemu -serial /dev/mydev ... But I would like to
> modify the libvirt definition XML file (in /etc/libvirt/qemu). Stefan notes in his blog
> (http://blog.vmsplice.net/2011/04/how-to-pass-qemu-command-line-options.html) that the options will
> look like:


---------- Forwarded message ----------
Date: Wed, 28 May 2014 18:06:10 +0300
From: Eric Blake <eblake at redhat.com>
To: Alexander Binun <binun at cs.bgu.ac.il>
Cc: Stefan Hajnoczi <stefanha at gmail.com>
   yagel at cs.bgu.ac.il
   kahilm at post.bgu.ac.il
   qemu-devel at nongnu.org
   boaz.menuhin at gmail.com
   Paolo Bonzini <pbonzini at redhat.com>
   markbl at post.bgu.ac.il
Subject: Re: excuse me for incorrect question...


On 05/28/2014 08:43 AM, Alexander Binun wrote:
> Eric, I aplogize for making your work complicated.

[You top-posted again]

No need to apologize - these lists exist to help people, and we were all
new once.

> 
> Should I send questions to libvirt-users at redhat.com instead ? I would ask more questions.

Yes, if your questions are related to libvirt, then asking on a libvirt
list will get you a better audience that may have better answers to your
questions.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


-------------- next part --------------

On 05/28/2014 08:43 AM, Alexander Binun wrote:
> Eric, I aplogize for making your work complicated.

[You top-posted again]

No need to apologize - these lists exist to help people, and we were all
new once.

> 
> Should I send questions to libvirt-users at redhat.com instead ? I would ask more questions.

Yes, if your questions are related to libvirt, then asking on a libvirt
list will get you a better audience that may have better answers to your
questions.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org