Re: [Qemu-devel] [Qemu-block] [PATCH COLO-Block v6 07/16] Add new block driver interface to connect/disconnect the remote target

[Dr. David Alan Gilbert]

* Wen Congyang (address@hidden) wrote:
> On 06/27/2015 03:03 AM, Dr. David Alan Gilbert wrote:

<snip>

> > Ah, I hadn't realised you could do that; so do you just do:
> > 
> > migrate_set_parameter colo on
> > migrate -d -b tcp:otherhhost:port
> > 
> > How does the secondary know to feed that data straight into the disk without
> > recording all the old data into the hidden-disk ?
> 
> hidden disk and active disk will be made empty when starting block 
> replication.

Hmm, yes - I think I need to update to your current world; in the version
from the end of May, I get a 'error while loading state for instance 0x0 of 
device 'block''
if I try to use migrate -d -b 
(the bdrv_write fails)

> >> If the user uses mirror job, we don't cancel the mirror job now.
> > 
> > It would be good to get it to work with mirror, that seems preferred these
> > days to the old block migration.
> 
> In normal migration, is mirror job created and cancelled by libvirt?

Yes, I think so; you should be able to turn on full logging on libvirt and
watch the qmp commands it sends.

Dave

--
Dr. David Alan Gilbert / address@hidden / Manchester, UK