Hi,
today I was trying to use the --copy-storage-all feature of virsh
migrate, in an attempt to migrate KVM-instances to another storage
backend. Doing so, I ran into some trouble:
First of all, it turned out the disk image-file has to be present on the
receiving end of the migration. When, just to check, this disk image is
smaller than the original image, migration suddenly stops (after filling
the maximum size of the too small disk image). This is expected
behaviour ofcourse.
But when I fix the disk image to the right size and start the migration
again, the migration fails immediately, the domain is -undefined- and
crashes. Qemu log showed:
kvm: block.c:2889: bdrv_set_in_use: Assertion `bs->in_use != in_use' failed.
2011-12-09 10:58:16.211: shutting down
Is this behaviour known to you guys?
Also, when I migrate a domain (10G qcow2 disk image, which is only used
for 1GB), the qcow2 image on the receiving end shows 10G for both
'virtual disk' and 'disk size', while this was 10G and 1G respectively
on the sending end. Why is the image expanded? Or is this a limitation
of the copy-storage-all?
How does the copy-storage-all function works for raw disk images? Does
it send incremental copies of blocks which are written too since the
migration is started?
Thanks in advance for your help!
Reinier Schoof
--
TransIP BV |
https://www.transip.nl/