Re: [Qemu-devel] [PATCH COLO-BLOCK v7 00/17] Block replication for continuous checkpoints

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Wen Congyang (wency@cn.fujitsu.com) wrote:
> On 07/07/2015 08:25 AM, Michael R. Hines wrote:
> > On 07/04/2015 07:46 AM, Wen Congyang wrote:
> >> At 2015/7/3 23:30, Dr. David Alan Gilbert Wrote:
> >>> * Wen Congyang (wency@cn.fujitsu.com) wrote:
> >>>> Block replication is a very important feature which is used for
> >>>> continuous checkpoints(for example: COLO).
> >>>>
> >>>> Usage:
> >>>> Please refer to docs/block-replication.txt
> >>>>
> >>>> You can get the patch here:
> >>>> https://github.com/wencongyang/qemu-colo/commits/block-replication-v7
> >>>>
> >>>> You can get ths patch with framework here:
> >>>> https://github.com/wencongyang/qemu-colo/commits/colo_framework_v7.2
> >>>
> >>> Hi,
> >>>    I seem to be having problems with the new listed syntax on the wiki;
> >>> on the secondary I'm getting the error
> >>>
> >>>   Block format 'replication' used by device 'virtio0' doesn't support the option 'export'
> >>>
> >>> ./try/bin/qemu-system-x86_64 -enable-kvm -nographic \
> >>>       -boot c -m 4096 -smp 4 -S \
> >>>       -name debug-threads=on -trace events=trace-file \
> >>>       -netdev tap,id=hn0,script=$PWD/ifup-slave,\
> >>> downscript=no,colo_script=$PWD/qemu/scripts/colo-proxy-script.sh,colo_nicname=em4 \
> >>>       -device e1000,mac=9c:da:4d:1c:b5:89,id=net-pci0,netdev=hn0 \
> >>>       -device virtio-rng-pci \
> >>>       -drive if=none,driver=raw,file=/home/localvms/bugzilla.raw,id=colo1,cache=none,aio=native \
> >>>       -drive if=virtio,driver=replication,mode=secondary,export=colo1,throttling.bps-total-max=70000000,\
> >>> file.file.filename=$TMPDISKS/colo-active-disk.qcow2,\
> >>> file.driver=qcow2,\
> >>> file.backing.file.filename=$TMPDISKS/colo-hidden-disk.qcow2,\
> >>> file.backing.driver=qcow2,\
> >>> file.backing.backing.backing_reference=colo1,\
> >>> file.backing.allow-write-backing-file=on \
> >>>       -incoming tcp:0:8888
> >>
> >> Sorry, the option export is removed, because we use the qmp command nbd-server-add to let a BB be NBD server.
> >>
> > 
> > Still doesn't work. The server says:
> > 
> > nbd.c:nbd_receive_options():L447: read failed
> 
> This log is very stange. The NBD client connects to NBD server, and NBD server wants to read data
> from NBD client, but reading fails. It seems that the connection is closed unexpectedly. Can you
> give me more log and how do you use it?

That was the same failure I was getting.   I think it's that the NBD server and client are in different
modes, with one of them expecting the export.

Dave

> Thanks
> Wen Congyang
> 
> > nbd.c:nbd_send_negotiate():L562: option negotiation failed
> > 
> > - Michael
> > 
> > .
> > 
> 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK