[libvirt-users] Live blockcopy onto storage pool that is an NFS mount?

[Andrew Martin]

----- Original Message -----
> From: "Eric Blake" <eblake at redhat.com>
> To: "Andrew Martin" <amartin at xes-inc.com>, libvirt-users at redhat.com
> Sent: Friday, August 1, 2014 4:40:28 PM
> Subject: Re: [libvirt-users] Live blockcopy onto storage pool that is an NFS mount?
> 
> > 
> > However when I attempt the blockcopy command, I receive this error:
> > Failed to create file '/var/lib/libvirt/images/nfs2/vm.qcow2': Operation
> > not permitted
> 
> Hmm, I know we've had problems in the past about labeling NFS files
> correctly, particularly when root squash is in play.  Do you have root
> squash turned on in your NFS servers?  If so, can you turn it off, and
> see if that improves the situation?  Also, libvirt 1.0.2 is a bit old;
> you may be encountering a bug that has been fixed in the meantime.
> Would you mind retrying with 1.2.7-rc2, to see if we need a last-minute
> bug-fix before this weekend's release of 1.2.7?
> 
> --
Eric,

Thanks for the help. Mounting the NFS exports with no_root_squash solved
the problem! In fact, I was able to successfully blockpull from one NFS
mountpoint to another with only these steps (without making it transient):
virsh snapshot-create-as --domain <vm_name> --disk-only --atomic --no-metadata --diskspec vda,snapshot=external,file=/path/to/nfs1/<vm_name>.qcow2
virsh blockpull --domain <vm_name> --path /path/to/nfs2/<vm_name>.qcow2

Since this works in libvirt 1.0.2 I imagine it will work just as well in
libvirt 1.2.7 as well.

Thanks,

Andrew