libvirt users - Feb 2017 - Re: Redhat 7: cgroup CPUACCT controller is not mounted

Thanks Martin to confirm that the issue is due to privilege access. How can I
run a domain as non-root and be able to access the cpu information?

-----Original Message-----
From: Martin Kletzander [mailto:mkletzan@redhat.com] 
Sent: Tuesday, February 28, 2017 16:18
To: EL FATHI Youssef OBS/OINIS
Cc: libvirt-users@redhat.com
Subject: Re: [libvirt-users] Redhat 7: cgroup CPUACCT controller is not mounted

On Mon, Feb 27, 2017 at 01:44:44PM +0000, youssef.elfathi@orange.com
wrote:
>Hi,
>
>With a non-root user account, I am launching virtual machines and would like
to get CPU stats for each Core (using python API or not) but face the following
problem:
>
>- When I issue the command "virsh --readonly cpu-stats MY_DOMAIN"
I got the following error:
>
>error: Failed to retrieve CPU statistics for domain 'MY_DOMAIN'
>error: Requested operation is not valid: cgroup CPUACCT controller is 
>not mounted
>
Since you are running the domain in session mode (non-root), libvirtd
doesn't have the privileges for creating a mount point for the domain and
hence the controller is available to use.  So I guess it's just a matter of
the error message being ambiguous.

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On Tue, Feb 28, 2017 at 03:22:54PM +0000, youssef.elfathi@orange.com
wrote:
>Thanks Martin to confirm that the issue is due to privilege access. How can
I run a domain as non-root and be able to access the cpu information?
>
You need to use the system libvirt daemon, so you need to connect to
qemu:///system instead of qemu:///session.  Good write-up about the
differences is here:

  http://blog.wikichoon.com/2016/01/qemusystem-vs-qemusession.html

There are also links to more info.

Thanks Martin, it resolved my issue. I had to adapt my setup to allow the
non-root user to use libvirt!

-----Original Message-----
From: Martin Kletzander [mailto:mkletzan@redhat.com] 
Sent: mardi 28 février 2017 19:07
To: EL FATHI Youssef OBS/OINIS <youssef.elfathi@orange.com>
Cc: libvirt-users@redhat.com
Subject: Re: [libvirt-users] Redhat 7: cgroup CPUACCT controller is not mounted

On Tue, Feb 28, 2017 at 03:22:54PM +0000, youssef.elfathi@orange.com
wrote:
>Thanks Martin to confirm that the issue is due to privilege access. How can
I run a domain as non-root and be able to access the cpu information?
>
You need to use the system libvirt daemon, so you need to connect to
qemu:///system instead of qemu:///session.  Good write-up about the differences
is here:

  http://blog.wikichoon.com/2016/01/qemusystem-vs-qemusession.html

There are also links to more info.

_________________________________________________________________________________________________________________________

Ce message et ses pieces jointes peuvent contenir des informations
confidentielles ou privilegiees et ne doivent donc
pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce
message par erreur, veuillez le signaler
a l'expediteur et le detruire ainsi que les pieces jointes. Les messages
electroniques etant susceptibles d'alteration,
Orange decline toute responsabilite si ce message a ete altere, deforme ou
falsifie. Merci.

This message and its attachments may contain confidential or privileged
information that may be protected by law;
they should not be distributed, used or copied without authorisation.
If you have received this email in error, please notify the sender and delete
this message and its attachments.
As emails may be altered, Orange is not liable for messages that have been
modified, changed or falsified.
Thank you.