CA-420533: Only clear RestartVM guidance on up-to-date hosts #6782
Conversation
gangj
force-pushed
the
private/gangj/CA-420533
branch
2 times, most recently
from
cff51af to
ba48b75
Compare
ocaml/xapi/xapi_vm_lifecycle.ml
Outdated
| remove_pending_guidance ~__context ~self ~value:`restart_device_model ; | ||
| remove_pending_guidance ~__context ~self ~value:`restart_vm | ||
| (* Only remove RestartVM guidance if host is up-to-date with coordinator *) | ||
| let resident_on = Db.VM.get_resident_on ~__context ~self in |
There was a problem hiding this comment.
This is in the branch of "state = `Halted". If the VM can't start on a host whose running xapi version lower than the one on the coordinator, this will not be necessary.
There was a problem hiding this comment.
Yes, it is a great question!
After a VM is Halted on an up-to-date host, does it still required for it to be started on an up-to-date host to clear the RestartVM guidance?
I think it should be yes? Then we can't clear the RestartVM guidance here at all?
There was a problem hiding this comment.
If the VM can't start on a host whose running xapi version lower than the one on the coordinator
I think it can only reboot in this case, where the host has is "older". That is where we should not clear the restart guidance. Starting on such a host is not allowed, so if a VM becomes halted, then the guidance can be removed.
There was a problem hiding this comment.
So I think the change here should be removed, while we keep only the conditional in xapi_xenops.ml that handles the start and reboot case.
There was a problem hiding this comment.
Sorry, @robhoes
So I think the change here should be removed
Do you mean we should not change xapi_vm_lifecycle.ml this time, and keep it always remove `restart_vm guidance?
Starting on such a host is not allowed
What if the VM is halted on an old host and then will the VM be allowed to start on the same old host again?
There was a problem hiding this comment.
Do you mean we should not change xapi_vm_lifecycle.ml this time, and keep it always remove `restart_vm guidance?
Yes I think so: for the case where the power_state will be halted.
What if the VM is halted on an old host and then will the VM be allowed to start on the same old host again?
No, because VM.start_on calls Helpers.Checks.RPU.assert_host_has_highest_version_in_pool in message_forwarding.
There was a problem hiding this comment.
Ah, sorry, I see, thank you!
gangj
force-pushed
the
private/gangj/CA-420533
branch
from
ba48b75 to
6db176c
Compare
During rolling pool upgrade (RPU), RestartVM guidance should only be cleared when a VM restarts on a host that has been updated to match the coordinator's software version. Previously, the guidance was cleared whenever a VM restarted, regardless of the host's update status. This commit ensures that RestartVM guidance persists until the VM restarts on an up-to-date host, this provides accurate feedback to administrators about which VMs still need restarting after RPU. Also adds unit tests covering 6 scenarios: * VM start on updated vs old host (via xenopsd) * Suspended VM resume on updated vs old host * VM halt on updated vs old host (via force_state_reset) Signed-off-by: Gang Ji <gang.ji@cloud.com>
gangj
force-pushed
the
private/gangj/CA-420533
branch
from
6db176c to
f905d64
Compare
3 participants
During rolling pool upgrade (RPU), RestartVM guidance should only be cleared when a VM restarts on a host that has been updated to match the coordinator's software version. Previously, the guidance was cleared whenever a VM restarted, regardless of the host's update status.
This commit ensures that RestartVM guidance persists until the VM restarts on an up-to-date host, this provides accurate feedback to administrators about which VMs still need restarting after RPU.
Also adds unit tests covering 6 scenarios: