[libvirt-users] Clarification about virsh migration options

[Berend Dekens]

On 02/12/2011 09:41 AM, Justin Clift wrote:
> This might help explain the difference as well:
>
>    http://wiki.libvirt.org/page/VM_lifecycle#Transient_guest_domains_vs_Persistent_guest_domains
>
> There is also migration info on that page, but it's fairly basic so
> not sure how useful.  Worth checking, just in case though. :)

Cheers for the clarifications. I've been experimenting with 2 
Qemu+KVM+libvirt systems but I cannot get the block migration to work:

virsh # migrate --live ISPConfig qemu+ssh://192.168.2.9/system 
--tunnelled --p2p --persistent --copy-storage-all
error: internal error process exited while connecting to monitor: char 
device redirected to /dev/pts/5
qemu: could not open disk image /mnt/storage/Virtual 
Machines/KVM/ispconfig_drive.img: No such file or directory

I run the virsh on the current host and 192.168.2.9 is the new VM host. 
I see the following on the current host in message output:

Feb 16 14:57:54 cyberxps qemu: could not open disk image 
/mnt/storage/Virtual Machines/KVM/ispconfig_drive.img: No such file or 
directory
Feb 16 15:00:56 cyberxps libvirtd: 15:00:56.999: 2850: debug : 
remoteIO:10438 : internal error process exited while connecting to 
monitor: 15:00:17.990: debug : qemudInitCpuAffinity:2459 : Setting CPU 
affinity
Feb 16 15:00:56 cyberxps 15:00:17.991: debug : 
qemuSecurityDACSetProcessLabel:547 : Dropping privileges of VM to 114:123
Feb 16 15:00:56 cyberxps char device redirected to /dev/pts/5
Feb 16 15:00:56 cyberxps qemu: could not open disk image 
/mnt/storage/Virtual Machines/KVM/ispconfig_drive.img: No such file or 
directory

This looks to me like at some point the block migration is failing 
('internal error ... monitor'?), but why? On the target host I can only 
see the same error messages but no clues as to why it fails.

Regards,
Berend Dekens