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b=K9v8xRciS0zrVvsk5d6PAO7xec5eQi6DB/y0vB5WWweYfoXKdj/Jos5YYQi6NwrVq 34nPrjIkXfXIv69EADV+3kctdp58TDQrMQKgk0MGH+4J6d5Q2sYoSA8vmcXJ4q7W4t Nb7vfvd35IiGZlhMQwAzjBrfcNK2Ibc7lPnkcl68= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from luklap ([89.247.255.245]) by smtp.web.de (mrweb101 [213.165.67.124]) with ESMTPSA (Nemesis) id 0LxOQ2-1iMzWt2hp4-016u3J; Thu, 15 Aug 2019 20:49:05 +0200 Date: Thu, 15 Aug 2019 20:49:04 +0200 From: Lukas Straub To: qemu-devel Message-ID: <4a5ef4f67b6e40d65d71bbaa0e70796f0edea3a4.1565894837.git.lukasstraub2@web.de> In-Reply-To: References: MIME-Version: 1.0 X-Provags-ID: V03:K1:Ou2QDVB+3vmhMblJssg3dMdbig2VFkpICpeCl/Pq99VJXn0hjcA LkHS/FLgEUKQoGSGkfrGGloWMHkEvWzrWPBZH/vOHvcEsuJYV7XPn1w//wMJfavIlmWPm/3 xJ3YL0YN+s3qfiI0sIuFDZga4EQ/UB6X8WYd5xSuAQzBZjbsZUes1b3pPGk73igic5+gGEW 9GNi7SiUwBzzcify2t0tg== X-UI-Out-Filterresults: notjunk:1;V03:K0:MAyA27pyeqY=:TMztAuR2Ebn43p3ong0LQf fwwyad1Bt5cpJGCVf1m0M1aG6lNjA2TDlMLvKZZYr+Mk4R1qMYCQWW9j/f1jydMmCLYvpDwKs mB86gKvuXw9mjp6f2TOQ0SBWmWuBcV2Q3Czu9mGtGlaU9miIxxUHAFUdjCF6CzDzqrARNpYXM oSTv+dNvdT3HRCIB4tSLG726f87Bo4HSlJH4L/TFDFbGoK6ArDw65kzG806JDfN4g1viToA+U IGqUMzvRy34O7icvnX1Fpw3Ap0UTnanAtGKwa1ffVmb3dUBXdG8uxeAP1tBJ6BddfHWWuCvVZ idCFV8+gSbbLT89a/c56HZDmDWmAKSnfdtcT0DWTTaRtAfN0ZB2JxUzUv6bD/K9WMLw6cxQWU u8Qi/DL8DgjRo4zFI2NRmA28Z8eCCkDMKnBpIyjpYWwjisWwOqz/nhr2ieAnO+2s+a6jwhA5J +aoXWngYyHuXD6cYFQPRl9WqHySDhHb4zlL7oOqF3vHB4G5ZqrKXYHb31096bzRRam/pQudY9 IQODT0jlM94XVbGk0vsZtkQMJk/+kKFeprmyg79ruD44gjjMNnQeps+8a6wvT+7CbDw4pNmuf C3K5+9rKb1qMepG8JNj8+fWt5vhEZ/ojtCedME7p0X390F1ZnsnusPoxxpfJT71GsMrNaJXco 492HJml0mRlOT2y0hdkuIYAQCShATEXr/ouppmtNkqb2qGoRvfV/Vav7GBTwHOHvDjia6lAYB d48c4hjA+gozxr15qfmDW5gUIQVdzwoOrMZnzJ7TEph7YtWsTtLCtF/ljhYkmaArpbnYeRjN/ m0j446BsDNzwXY+Mhfuep7ZhONXN4Hu7fiaEYmEDknBp2z03785B8Xbzx5PHvt8ryhmR5yW+Z WOOpWJFfb2KvINRmyqFBUeSDlwSrPxzHhfxApXEYMQd1jsqLixkRmd3ZMnKR5RRtGi5+M8Aol VdeU1lDXTC6wowVLyYBuRvXJSoHsWFDBfYZOxoEBM0X81r/lidtaNBKOWpA7grnWGxaIBNATD HMbJGMCU73lNSiYGdZT5UNreBHf8z82MwNiAgkRx8k942SrV2GCWXGXGAkID8Z3U0bL0yGEkm rhQayAo2aFrvRG8D9SrliZ/aDiE2/4ngt0hoAhMB9Jj+1U4xFNz1nDC0zMSFy2v4POkwBo6Gv WwOj1dVQkk0nVxAS8vwYLDRmOpVnu7b6e8AEiG5W1ndzkzwXb2VW8cr16wteG49m9yshg= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 212.227.17.11 Subject: [Qemu-devel] [PATCH v2 3/3] Update Documentation X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Zhang Chen , Jason Wang , Xie Changlong , Wen Congyang Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP Document the qemu command-line and qmp commands for continious replication Signed-off-by: Lukas Straub --- docs/COLO-FT.txt | 185 +++++++++++++++++++++++++++++++++++------------ 1 file changed, 138 insertions(+), 47 deletions(-) diff --git a/docs/COLO-FT.txt b/docs/COLO-FT.txt index ad24680d13..c08bfbd3a8 100644 --- a/docs/COLO-FT.txt +++ b/docs/COLO-FT.txt @@ -145,35 +145,64 @@ The diagram just shows the main qmp command, you can get the detail in test procedure. == Test procedure == +Note: Here we are running both instances on the same Machine for testing, +change the IP Addresses if you want to run it on two Hosts + 1. Startup qemu Primary: -# qemu-system-x86_64 -accel kvm -m 2048 -smp 2 -qmp stdio -name primary \ - -device piix3-usb-uhci -vnc :7 \ - -device usb-tablet -netdev tap,id=hn0,vhost=off \ - -device virtio-net-pci,id=net-pci0,netdev=hn0 \ - -drive if=virtio,id=primary-disk0,driver=quorum,read-pattern=fifo,vote-threshold=1,\ - children.0.file.filename=1.raw,\ - children.0.driver=raw -S +# imagefolder="/mnt/vms/colo-test" + +# cp --reflink=auto $imagefolder/primary.qcow2 $imagefolder/primary-copy.qcow2 + +# qemu-system-x86_64 -enable-kvm -cpu qemu64,+kvmclock -m 512 -smp 1 -qmp stdio \ + -vnc :0 -k de -device piix3-usb-uhci -device usb-tablet -name primary \ + -netdev tap,id=hn0,vhost=off,helper=/usr/lib/qemu/qemu-bridge-helper \ + -device rtl8139,id=e0,netdev=hn0 \ + -chardev socket,id=mirror0,host=127.0.0.1,port=9003,server,nowait \ + -chardev socket,id=compare1,host=127.0.0.1,port=9004,server,wait \ + -chardev socket,id=compare0,host=127.0.0.1,port=9001,server,nowait \ + -chardev socket,id=compare0-0,host=127.0.0.1,port=9001 \ + -chardev socket,id=compare_out,host=127.0.0.1,port=9005,server,nowait \ + -chardev socket,id=compare_out0,host=127.0.0.1,port=9005 \ + -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 \ + -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out \ + -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 \ + -object iothread,id=iothread1 \ + -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,\ +outdev=compare_out0,iothread=iothread1 \ + -drive if=ide,id=colo-disk0,driver=quorum,read-pattern=fifo,vote-threshold=1,\ +children.0.file.filename=$imagefolder/primary.qcow2,children.0.driver=qcow2 -S + Secondary: -# qemu-system-x86_64 -accel kvm -m 2048 -smp 2 -qmp stdio -name secondary \ - -device piix3-usb-uhci -vnc :7 \ - -device usb-tablet -netdev tap,id=hn0,vhost=off \ - -device virtio-net-pci,id=net-pci0,netdev=hn0 \ - -drive if=none,id=secondary-disk0,file.filename=1.raw,driver=raw,node-name=node0 \ - -drive if=virtio,id=active-disk0,driver=replication,mode=secondary,\ - file.driver=qcow2,top-id=active-disk0,\ - file.file.filename=/mnt/ramfs/active_disk.img,\ - file.backing.driver=qcow2,\ - file.backing.file.filename=/mnt/ramfs/hidden_disk.img,\ - file.backing.backing=secondary-disk0 \ - -incoming tcp:0:8888 +# imagefolder="/mnt/vms/colo-test" + +# qemu-img create -f qcow2 $imagefolder/secondary-active.qcow2 10G + +# qemu-img create -f qcow2 $imagefolder/secondary-hidden.qcow2 10G + +# qemu-system-x86_64 -enable-kvm -cpu qemu64,+kvmclock -m 512 -smp 1 -qmp stdio \ + -vnc :1 -k de -device piix3-usb-uhci -device usb-tablet -name secondary \ + -netdev tap,id=hn0,vhost=off,helper=/usr/lib/qemu/qemu-bridge-helper \ + -device rtl8139,id=e0,netdev=hn0 \ + -chardev socket,id=red0,host=127.0.0.1,port=9003,reconnect=1 \ + -chardev socket,id=red1,host=127.0.0.1,port=9004,reconnect=1 \ + -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 \ + -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 \ + -object filter-rewriter,id=rew0,netdev=hn0,queue=all \ + -drive if=none,id=parent0,file.filename=$imagefolder/primary-copy.qcow2,driver=qcow2 \ + -drive if=none,id=childs0,driver=replication,mode=secondary,file.driver=qcow2,\ +top-id=childs0,file.file.filename=$imagefolder/secondary-active.qcow2,\ +file.backing.driver=qcow2,file.backing.file.filename=$imagefolder/secondary-hidden.qcow2,\ +file.backing.backing=parent0 \ + -drive if=ide,id=colo-disk0,driver=quorum,read-pattern=fifo,vote-threshold=1,\ +children.0.file=childs0,children.0.driver=raw \ + -incoming tcp:0:9998 + 2. 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': '127.0.0.1', '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 @@ -184,12 +213,10 @@ Note: 3. 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.xx,file.port=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=127.0.0.1,file.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:127.0.0.1:9998' } } Note: a. There should be only one NBD Client for each primary disk. @@ -199,27 +226,91 @@ Note: 4. 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 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. +You can kill one of the VMs and Failover on the surviving VM: -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 +== Primary Failover == +The Secondary died, resume on the Primary -Secondary: - The primary host is down, so we should do the following thing: - { 'execute': 'nbd-server-stop' } +{'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': '127.0.0.1', 'port': '9003' } }, 'server': true } } } } +{'execute': 'chardev-add', 'arguments':{ 'id': 'compare1', 'backend': {'type': 'socket', 'data': {'addr': { 'type': 'inet', 'data': { 'host': '127.0.0.1', '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, then: +{'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'} } + +{'execute': 'human-monitor-command', 'arguments':{ 'command-line': 'drive_add -n buddy driver=replication,mode=primary,file.driver=nbd,file.host=127.0.0.1,file.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:127.0.0.1:9998' } } + +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': 'rew0'" Options. See below. + +== Secondary resume replication == +Become Primary and resume replication after new Secondary is up. + +Start the new Secondary, then: +{'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' } } + +{'execute': 'human-monitor-command', 'arguments':{ 'command-line': 'drive_add -n buddy driver=replication,mode=primary,file.driver=nbd,file.host=127.0.0.1,file.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': { 'insert': 'before', 'position': 'rew0', 'netdev': 'hn0', 'queue': 'tx', 'outdev': 'mirror0' } } } +{'execute': 'object-add', 'arguments':{ 'qom-type': 'filter-redirector', 'id': 'redire0', 'props': { 'insert': 'before', 'position': 'rew0', 'netdev': 'hn0', 'queue': 'rx', 'indev': 'compare_out' } } } +{'execute': 'object-add', 'arguments':{ 'qom-type': 'filter-redirector', 'id': 'redire1', 'props': { 'insert': 'before', 'position': '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' } } } + +{'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.