[Bug 1881231] Re: colo: Can not recover colo after svm failover twice

[ye.zou]

In step 3 I used following commands:
on primary vm console:
{"execute": "drive-mirror", "arguments":{ "device": "colo-disk0", "job-id": 
"resync", "target": "nbd://169.254.66.10:9999/parent0", "mode": 
"existing","format":"raw","sync":"full"} }

// till the job ready
{ "execute": "query-block-jobs" }

{"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=169.254.66.10,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:169.254.66.10:9998' } }
{ "execute": "migrate-set-parameters" , "arguments":{ "x-checkpoint-delay": 
10000 } }

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1881231

Title:
  colo: Can not  recover colo after svm failover twice

Status in QEMU:
  New

Bug description:
  Hi Expert,
  x-blockdev-change met some error, during testing colo

  Host os:
  CentOS Linux release 7.6.1810 (Core)

  Reproduce steps:
  1. create colo vm following 
https://github.com/qemu/qemu/blob/master/docs/COLO-FT.txt
  2. kill secondary vm and remove the nbd child from the quorum to wait for 
recover
    type those commands on primary vm console:
    { 'execute': 'x-blockdev-change', 'arguments': {'parent': 'colo-disk0', 
'child': 'children.1'}}
    { 'execute': 'human-monitor-command','arguments': {'command-line': 
'drive_del replication0'}}
    { 'execute': 'x-colo-lost-heartbeat'}
  3. recover colo
  4. kill secondary vm again after recover colo and type same commands as step 
2:
    { 'execute': 'x-blockdev-change', 'arguments': {'parent': 'colo-disk0', 
'child': 'children.1'}}
    { 'execute': 'human-monitor-command','arguments': {'command-line': 
'drive_del replication0'}}
    { 'execute': 'x-colo-lost-heartbeat'}
    but the first command got error
    { 'execute': 'x-blockdev-change', 'arguments': {'parent': 'colo-disk0', 
'child': 'children.1'}}
  {"error": {"class": "GenericError", "desc": "Node 'colo-disk0' does not have 
child 'children.1'"}}

  according to https://www.qemu.org/docs/master/qemu-qmp-ref.html
  Command: x-blockdev-change
  Dynamically reconfigure the block driver state graph. It can be used to add, 
remove, insert or replace a graph node. Currently only the Quorum driver 
implements this feature to add or remove its child. This is useful to fix a 
broken quorum child.

  It seems x-blockdev-change not worked as expected.

  Thanks.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1881231/+subscriptions