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Re: [OpenStack][Nova] Live Migration + NFSv4 - Permission issues

 

Ok. so i have added the option you mentioned, restarted nfs and remounted
on the compute nodes.

Now i get this error: http://paste.openstack.org/show/19260/

:S

On Wed, Jul 4, 2012 at 4:18 PM, Daniel P. Berrange <berrange@xxxxxxxxxx>wrote:

> On Tue, Jul 03, 2012 at 02:48:05PM +0100, Leander Bessa Beernaert wrote:
> > Hello all,
> >
> > I've been trying to get the live migration to work according to the guide
> >
> http://docs.openstack.org/trunk/openstack-compute/admin/content/configuring-live-migrations.html
> .
> >
> > So far i've setup 2 compute nodes and 1 controller node. They all share
> the
> > /var/lib/nova/instances dir. I've already verified that the nova user id
> is
> > the same across all the servers.
> >
> > Currently i'm running into this error when i launch an instance:
> > http://paste.openstack.org/show/19221/
> >
> > It's certainly a permission issue, so i tried adding the group "nova" to
> > the user "libvirt-qemu". However, it still doesn't work. To which user
> must
> > i give the nova group permission in order to be able to write in that
> > directory?
>
> So the error message you get here:
>
>   libvirtError: Unable to pre-create chardev file
> '/var/lib/nova/instances/instance-00000004/console.log': Permission denied
>
> is coming from the libvirt QEMU driver code. This code runs as root:root
> in the libvirtd daemon. As such, ordinarily permissions would not be a
> problem that blocks libvirtd doing what it wants. NFS is horrible /
> special though, and has this capability "root squash" which causes any
> client host processes running as root to be treated as if they were
> running as 'nfsnobody' or a similar unprivileged user.  So if you want
> libvirtd to be able to use this mount point you'll need to make sure
> that your NFS server has root squash disabled. eg by adding the option
> 'no_root_squash' to the /etc/exports file for that mount.
>
>
> Daniel
> --
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>

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