troubles copying qcow2 VM images

[Serge E. Hallyn]

Quoting jurgen.depicker at let.be (jurgen.depicker at let.be):
> Dear all,
> 
> I'm facing a weird situation, trying to migrate from one storage pool (on 
> VLET1, SWRAID1,SATA) to another (on VLET3, HWRAID1,SAS)
> (all servers VLET1,2,3 on ubuntu 10.10)
> 
> 1. I stop all running VM instances
> 2. On VLET3, I have an NFS share of VLET1 mounted
> 3. On VLET3, I issue: cp /mnt/nfs/VM1.qcow2  /srv/VMs/
> 4. I reconfigure VM1 to use the newly created copied /srv/VMs/VM1.qcow2
> 
> -> it gets mounted read-only apparently; it doesn't work.  When using 
> rsync instead of cp, there's no difference...  I really don't understand 
> what's going on...  Who has a clue please??

Can you sha1sum {/mnt/nfs,/srv/VMs/}/VM1.qcow2?  My guess is this is an
NFS bug with large file xfer corruption.

-serge