> -----Original Message----- > From: Lukas Straub <lukasstra...@web.de> > Sent: Wednesday, October 9, 2019 11:17 PM > To: Zhang, Chen <chen.zh...@intel.com> > Cc: qemu-devel <qemu-de...@nongnu.org>; Jason Wang > <jasow...@redhat.com>; Wen Congyang <wencongya...@huawei.com>; > Xie Changlong <xiechanglon...@gmail.com>; Kevin Wolf > <kw...@redhat.com>; Max Reitz <mre...@redhat.com>; qemu-block > <qemu-block@nongnu.org> > Subject: Re: [PATCH v6 4/4] colo: Update Documentation for continuous > replication > > On Wed, 9 Oct 2019 08:36:52 +0000 > "Zhang, Chen" <chen.zh...@intel.com> wrote: > > > > -----Original Message----- > > > From: Lukas Straub <lukasstra...@web.de> > > > Sent: Saturday, October 5, 2019 9:06 PM > > > To: qemu-devel <qemu-de...@nongnu.org> > > > Cc: Zhang, Chen <chen.zh...@intel.com>; Jason Wang > > > <jasow...@redhat.com>; Wen Congyang > <wencongya...@huawei.com>; Xie > > > Changlong <xiechanglon...@gmail.com>; Kevin Wolf > <kw...@redhat.com>; > > > Max Reitz <mre...@redhat.com>; qemu-block <qemu- > bl...@nongnu.org> > > > Subject: [PATCH v6 4/4] colo: Update Documentation for continuous > > > replication > > > > > > Document the qemu command-line and qmp commands for continuous > > > replication > > > > > > Signed-off-by: Lukas Straub <lukasstra...@web.de> > > > --- > > > docs/COLO-FT.txt | 213 +++++++++++++++++++++++++++---------- > > > docs/block-replication.txt | 28 +++-- > > > 2 files changed, 174 insertions(+), 67 deletions(-) > > > > > > diff --git a/docs/COLO-FT.txt b/docs/COLO-FT.txt index > > > ad24680d13..bc1a0ccb99 100644 > > > --- a/docs/COLO-FT.txt > > > +++ b/docs/COLO-FT.txt > > > @@ -145,35 +145,65 @@ The diagram just shows the main qmp > command, > > > you can get the detail in test procedure. > > > > > > ... > > > > > > +Note: Here we are running both instances on the same Host for > > > +testing, change the IP Addresses if you want to run it on two > > > +Hosts. Initally > > > +127.0.0.1 is the Primary Host and 127.0.0.2 is the Secondary Host. > > > + > > > +== Startup qemu == > > > +1. Primary: > > > +Note: Initally, $imagefolder/primary.qcow2 needs to be copied to all > Hosts. > > > +# imagefolder="/mnt/vms/colo-test-primary" > > > + > > > +# qemu-system-x86_64 -enable-kvm -cpu qemu64,+kvmclock -m 512 - > smp > > > 1 -qmp stdio \ > > > + -device piix3-usb-uhci -device usb-tablet -name primary \ > > > + -netdev > > > + tap,id=hn0,vhost=off,helper=/usr/lib/qemu/qemu-bridge-helper > > > \ > > > + -device rtl8139,id=e0,netdev=hn0 \ > > > + -chardev socket,id=mirror0,host=0.0.0.0,port=9003,server,nowait \ > > > + -chardev socket,id=compare1,host=0.0.0.0,port=9004,server,wait \ > > > > We should change the host=127.0.0.1 consistent with the expression below. > > Hi, > This (and the IPs below in the QMP commands) needs to be this way, > because it's a listening port and with 127.0.0.1 it would only listen on the > loopback ip and wouldn't be reachable from another node for example. With > 0.0.0.0 it will listen on all Interfaces.
Yes, I know. For this command demo, maybe use 192.168.0.1/192.168.0.2 are more clear. > > > > + -chardev socket,id=compare0,host=127.0.0.1,port=9001,server,nowait > \ > > > + -chardev socket,id=compare0-0,host=127.0.0.1,port=9001 \ > > > + -chardev > > > + socket,id=compare_out,host=127.0.0.1,port=9005,server,nowait > > > \ > > > + -chardev socket,id=compare_out0,host=127.0.0.1,port=9005 \ > > > + -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 \ > > > + -object filter- > > > redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out \ > > > + -object filter- > > > redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 \ > > > + -object iothread,id=iothread1 \ > > > + -object > > > +colo-compare,id=comp0,primary_in=compare0- > > > 0,secondary_in=compare1,\ > > > +outdev=compare_out0,iothread=iothread1 \ > > > + -drive > > > +if=ide,id=colo-disk0,driver=quorum,read-pattern=fifo,vote-threshold > > > +=1,\ > > > +children.0.file.filename=$imagefolder/primary.qcow2,children.0.driv > > > +er=q > > > +cow2 -S > > > + > > > +2. Secondary: > > > +# imagefolder="/mnt/vms/colo-test-secondary" > > > +# primary_ip=127.0.0.1 > > > + > > > +# qemu-img create -f qcow2 $imagefolder/secondary-active.qcow2 10G > > > + > > > +# qemu-img create -f qcow2 $imagefolder/secondary-hidden.qcow2 > 10G > > > + > > > > The active disk and hidden disk just need create one time, we can note that > here. > > Ok, I will Note that. But I will wait until the block changes are reviewed > before sending the next version. That's fine for me. Thanks Zhang Chen > > Regards, > Lukas Straub > > > > +# qemu-system-x86_64 -enable-kvm -cpu qemu64,+kvmclock -m 512 - > smp > > > 1 -qmp stdio \ > > > + -device piix3-usb-uhci -device usb-tablet -name secondary \ > > > + -netdev > > > + tap,id=hn0,vhost=off,helper=/usr/lib/qemu/qemu-bridge-helper > > > \ > > > + -device rtl8139,id=e0,netdev=hn0 \ > > > + -chardev socket,id=red0,host=$primary_ip,port=9003,reconnect=1 \ > > > + -chardev socket,id=red1,host=$primary_ip,port=9004,reconnect=1 \ > > > + -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 \ > > > + -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 \ > > > + -object filter-rewriter,id=rew0,netdev=hn0,queue=all \ > > > + -drive > > > if=none,id=parent0,file.filename=$imagefolder/primary.qcow2,driver=q > > > cow > > > 2 \ > > > + -drive > > > +if=none,id=childs0,driver=replication,mode=secondary,file.driver=qc > > > +ow2, > > > +\ > > > +top-id=childs0,file.file.filename=$imagefolder/secondary-active.qco > > > +w2,\ > > > +file.backing.driver=qcow2,file.backing.file.filename=$imagefolder/s > > > +econ > > > +dary-hidden.qcow2,\ > > > +file.backing.backing=parent0 \ > > > + -drive > > > +if=ide,id=colo-disk0,driver=quorum,read-pattern=fifo,vote-threshold > > > +=1,\ > > > +children.0=childs0 \ > > > + -incoming tcp:0.0.0.0:9998 > > > + > > > + > > > +3. On Secondary VM's QEMU monitor, issue command > > > {'execute':'qmp_capabilities'} > > > -{ 'execute': 'nbd-server-start', > > > - 'arguments': {'addr': {'type': 'inet', 'data': {'host': 'xx.xx.xx.xx', > > > 'port': > > > '8889'} } } -} > > > -{'execute': 'nbd-server-add', 'arguments': {'device': > > > 'secondary-disk0', > > > 'writable': true } } > > > +{'execute': 'nbd-server-start', 'arguments': {'addr': {'type': > > > +'inet', > > > +'data': {'host': '0.0.0.0', 'port': '9999'} } } } > > > +{'execute': 'nbd-server-add', 'arguments': {'device': 'parent0', > > > +'writable': true } } > > > > > > Note: > > > a. The qmp command nbd-server-start and nbd-server-add must be > > > run @@ -182,44 +212,113 @@ Note: > > > same. > > > c. It is better to put active disk and hidden disk in ramdisk. > > > > > > -3. On Primary VM's QEMU monitor, issue command: > > > +4. On Primary VM's QEMU monitor, issue command: > > > {'execute':'qmp_capabilities'} > > > -{ 'execute': 'human-monitor-command', > > > - 'arguments': {'command-line': 'drive_add -n buddy > > > driver=replication,mode=primary,file.driver=nbd,file.host=xx.xx.xx.x > > > x,file.p > > > ort=8889,file.export=secondary-disk0,node-name=nbd_client0'}} > > > -{ 'execute':'x-blockdev-change', 'arguments':{'parent': > > > 'primary-disk0', > > > 'node': 'nbd_client0' } } -{ 'execute': 'migrate-set-capabilities', > > > - 'arguments': {'capabilities': [ {'capability': 'x-colo', 'state': > > > true } ] } } > > > -{ 'execute': 'migrate', 'arguments': {'uri': 'tcp:xx.xx.xx.xx:8888' > > > } } > > > +{'execute': 'human-monitor-command', 'arguments': {'command-line': > > > +'drive_add -n buddy > > > +driver=replication,mode=primary,file.driver=nbd,file.host=127.0.0.2 > > > +,fil e.port=9999,file.export=parent0,node-name=replication0'}} > > > +{'execute': 'x-blockdev-change', 'arguments':{'parent': > > > +'colo-disk0', > > > +'node': 'replication0' } } > > > +{'execute': 'migrate-set-capabilities', 'arguments': > > > +{'capabilities': [ > > > +{'capability': 'x-colo', 'state': true } ] } } > > > +{'execute': 'migrate', 'arguments': {'uri': 'tcp:127.0.0.2:9998' } > > > +} > > > > > > Note: > > > a. There should be only one NBD Client for each primary disk. > > > - b. xx.xx.xx.xx is the secondary physical machine's hostname or IP > > > - c. The qmp command line must be run after running qmp command > > > line in > > > + b. The qmp command line must be run after running qmp command > > > + line in > > > secondary qemu. > > > > > > -4. After the above steps, you will see, whenever you make changes > > > to PVM, SVM will be synced. > > > +5. After the above steps, you will see, whenever you make changes > > > +to PVM, > > > SVM will be synced. > > > You can issue command '{ "execute": "migrate-set-parameters" , > > > "arguments":{ "x-checkpoint-delay": 2000 } }' > > > -to change the checkpoint period time > > > +to change the idle checkpoint period time > > > + > > > +6. Failover test > > > +You can kill one of the VMs and Failover on the surviving VM: > > > + > > > +If you killed the Secondary, then follow "Primary Failover". After > > > +that, if you want to resume the replication, follow "Primary resume > > > replication" > > > + > > > +If you killed the Primary, then follow "Secondary Failover". After > > > +that, if you want to resume the replication, follow "Secondary > > > +resume > > > replication" > > > + > > > +== Primary Failover == > > > +The Secondary died, resume on the Primary > > > + > > > +{'execute': 'x-blockdev-change', 'arguments':{ 'parent': > > > +'colo-disk0', > > > +'child': 'children.1'} } > > > +{'execute': 'human-monitor-command', 'arguments':{ 'command-line': > > > +'drive_del replication0' } } > > > +{'execute': 'object-del', 'arguments':{ 'id': 'comp0' } } > > > +{'execute': 'object-del', 'arguments':{ 'id': 'iothread1' } } > > > +{'execute': 'object-del', 'arguments':{ 'id': 'm0' } } > > > +{'execute': 'object-del', 'arguments':{ 'id': 'redire0' } } > > > +{'execute': 'object-del', 'arguments':{ 'id': 'redire1' } } > > > +{'execute': 'x-colo-lost-heartbeat' } > > > + > > > +== Secondary Failover == > > > +The Primary died, resume on the Secondary and prepare to become the > > > new > > > +Primary > > > + > > > +{'execute': 'nbd-server-stop'} > > > +{'execute': 'x-colo-lost-heartbeat'} > > > + > > > +{'execute': 'object-del', 'arguments':{ 'id': 'f2' } } > > > +{'execute': 'object-del', 'arguments':{ 'id': 'f1' } } > > > +{'execute': 'chardev-remove', 'arguments':{ 'id': 'red1' } } > > > +{'execute': 'chardev-remove', 'arguments':{ 'id': 'red0' } } > > > + > > > +{'execute': 'chardev-add', 'arguments':{ 'id': 'mirror0', 'backend': > > > +{'type': 'socket', 'data': {'addr': { 'type': 'inet', 'data': { 'host': > > > +'0.0.0.0', 'port': '9003' } }, 'server': true } } } } > > > > Same like I said before. > > > > Others statement looks good for me. > > > > Thanks > > Zhang Chen > > > > > +{'execute': 'chardev-add', 'arguments':{ 'id': 'compare1', 'backend': > > > +{'type': 'socket', 'data': {'addr': { 'type': 'inet', 'data': { 'host': > > > +'0.0.0.0', 'port': '9004' } }, 'server': true } } } } > > > +{'execute': 'chardev-add', 'arguments':{ 'id': 'compare0', 'backend': > > > +{'type': 'socket', 'data': {'addr': { 'type': 'inet', 'data': { 'host': > > > +'127.0.0.1', 'port': '9001' } }, 'server': true } } } } > > > +{'execute': 'chardev-add', 'arguments':{ 'id': 'compare0-0', 'backend': > > > +{'type': 'socket', 'data': {'addr': { 'type': 'inet', 'data': { 'host': > > > +'127.0.0.1', 'port': '9001' } }, 'server': false } } } } > > > +{'execute': 'chardev-add', 'arguments':{ 'id': 'compare_out', > > > +'backend': {'type': 'socket', 'data': {'addr': { 'type': 'inet', > > > +'data': { 'host': '127.0.0.1', 'port': '9005' } }, 'server': true } > > > +} } } > > > +{'execute': 'chardev-add', 'arguments':{ 'id': 'compare_out0', > > > +'backend': {'type': 'socket', 'data': {'addr': { 'type': 'inet', > > > +'data': { 'host': '127.0.0.1', 'port': '9005' } }, 'server': false > > > +} } } } > > > + > > > +== Primary resume replication == > > > +Resume replication after new Secondary is up. > > > + > > > +Start the new Secondary (Steps 2 and 3 above), then on the Primary: > > > +{'execute': 'drive-mirror', 'arguments':{ 'device': 'colo-disk0', > > > +'job-id': 'resync', 'target': 'nbd://127.0.0.2:9999/parent0', 'mode': > > > +'existing', 'format': 'raw', 'sync': 'full'} } > > > + > > > +Wait until disk is synced, then: > > > +{'execute': 'stop'} > > > +{'execute': 'block-job-cancel', 'arguments':{ 'device': 'resync'} } > > > + > > > +{'execute': 'human-monitor-command', 'arguments':{ 'command-line': > > > +'drive_add -n buddy > > > +driver=replication,mode=primary,file.driver=nbd,file.host=127.0.0.2 > > > +,fil e.port=9999,file.export=parent0,node-name=replication0'}} > > > +{'execute': 'x-blockdev-change', 'arguments':{ 'parent': > > > +'colo-disk0', > > > +'node': 'replication0' } } > > > + > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': > > > +'filter-mirror', > > > +'id': 'm0', 'props': { 'netdev': 'hn0', 'queue': 'tx', 'outdev': > > > +'mirror0' } } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': > > > +'filter-redirector', 'id': 'redire0', 'props': { 'netdev': 'hn0', > > > +'queue': 'rx', 'indev': 'compare_out' } } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': > > > +'filter-redirector', 'id': 'redire1', 'props': { 'netdev': 'hn0', > > > +'queue': 'rx', 'outdev': 'compare0' } } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': 'iothread', 'id': > > > +'iothread1' } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': 'colo-compare', > > > +'id': 'comp0', 'props': { 'primary_in': 'compare0-0', 'secondary_in': > > > +'compare1', 'outdev': 'compare_out0', 'iothread': 'iothread1' } } } > > > + > > > +{'execute': 'migrate-set-capabilities', 'arguments':{ > > > +'capabilities': [ > > > +{'capability': 'x-colo', 'state': true } ] } } > > > +{'execute': 'migrate', 'arguments':{ 'uri': 'tcp:127.0.0.2:9998' } > > > +} > > > + > > > +Note: > > > +If this Primary previously was a Secondary, then we need to insert > > > +the filters before the filter-rewriter by using the > > > +"'insert': 'before', 'position': 'id=rew0'" Options. See below. > > > + > > > +== Secondary resume replication == > > > +Become Primary and resume replication after new Secondary is up. > > > +Note that now 127.0.0.1 is the Secondary and 127.0.0.2 is the Primary. > > > + > > > +Start the new Secondary (Steps 2 and 3 above, but with > > > +primary_ip=127.0.0.2), then on the old Secondary: > > > +{'execute': 'drive-mirror', 'arguments':{ 'device': 'colo-disk0', > > > +'job-id': 'resync', 'target': 'nbd://127.0.0.1:9999/parent0', 'mode': > > > +'existing', 'format': 'raw', 'sync': 'full'} } > > > + > > > +Wait until disk is synced, then: > > > +{'execute': 'stop'} > > > +{'execute': 'block-job-cancel', 'arguments':{ 'device': 'resync' } > > > +} > > > > > > -5. Failover test > > > -You can kill Primary VM and run 'x_colo_lost_heartbeat' in > > > Secondary VM's - monitor at the same time, then SVM will failover > > > and client will not detect this -change. > > > +{'execute': 'human-monitor-command', 'arguments':{ 'command-line': > > > +'drive_add -n buddy > > > +driver=replication,mode=primary,file.driver=nbd,file.host=127.0.0.1 > > > +,fil e.port=9999,file.export=parent0,node-name=replication0'}} > > > +{'execute': 'x-blockdev-change', 'arguments':{ 'parent': > > > +'colo-disk0', > > > +'node': 'replication0' } } > > > > > > -Before issuing '{ "execute": "x-colo-lost-heartbeat" }' command, we > > > have to -issue block related command to stop block replication. > > > -Primary: > > > - Remove the nbd child from the quorum: > > > - { 'execute': 'x-blockdev-change', 'arguments': {'parent': 'colo-disk0', > 'child': > > > 'children.1'}} > > > - { 'execute': 'human-monitor-command','arguments': {'command-line': > > > 'drive_del blk-buddy0'}} > > > - Note: there is no qmp command to remove the blockdev now > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': > > > +'filter-mirror', > > > +'id': 'm0', 'props': { 'insert': 'before', 'position': 'id=rew0', > > > +'netdev': 'hn0', 'queue': 'tx', 'outdev': 'mirror0' } } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': > > > +'filter-redirector', 'id': 'redire0', 'props': { 'insert': > > > +'before', > > > +'position': 'id=rew0', 'netdev': 'hn0', 'queue': 'rx', 'indev': > > > +'compare_out' } } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': > > > +'filter-redirector', 'id': 'redire1', 'props': { 'insert': > > > +'before', > > > +'position': 'id=rew0', 'netdev': 'hn0', 'queue': 'rx', 'outdev': > > > +'compare0' } } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': 'iothread', 'id': > > > +'iothread1' } } > > > +{'execute': 'object-add', 'arguments':{ 'qom-type': 'colo-compare', > > > +'id': 'comp0', 'props': { 'primary_in': 'compare0-0', 'secondary_in': > > > +'compare1', 'outdev': 'compare_out0', 'iothread': 'iothread1' } } } > > > > > > -Secondary: > > > - The primary host is down, so we should do the following thing: > > > - { 'execute': 'nbd-server-stop' } > > > +{'execute': 'migrate-set-capabilities', 'arguments':{ > > > +'capabilities': [ > > > +{'capability': 'x-colo', 'state': true } ] } } > > > +{'execute': 'migrate', 'arguments':{ 'uri': 'tcp:127.0.0.1:9998' } > > > +} > > > > > > == TODO == > > > -1. Support continuous VM replication. > > > -2. Support shared storage. > > > -3. Develop the heartbeat part. > > > -4. Reduce checkpoint VM’s downtime while doing checkpoint. > > > +1. Support shared storage. > > > +2. Develop the heartbeat part. > > > +3. Reduce checkpoint VM’s downtime while doing checkpoint.