Bug 728341
Summary: | stopping src libvirtd during migration pauses the guest being migrated | ||
---|---|---|---|
Product: | Red Hat Enterprise Linux 7 | Reporter: | Dave Allan <dallan> |
Component: | libvirt | Assignee: | Jiri Denemark <jdenemar> |
Status: | CLOSED DEFERRED | QA Contact: | Virtualization Bugs <virt-bugs> |
Severity: | medium | Docs Contact: | |
Priority: | medium | ||
Version: | 7.0 | CC: | cwei, dyuan, mzhan, weizhan |
Target Milestone: | rc | ||
Target Release: | --- | ||
Hardware: | All | ||
OS: | All | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | Bug Fix | |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | 2014-08-07 12:31:23 UTC | Type: | --- |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: |
Description
Dave Allan
2011-08-04 18:45:16 UTC
It's because in normal (non-tunneled) migration libvirtd is not involved in the actual migration process. It just sets everything up, tells qemu to start migration and once that ends (successfully or not), libvirt resumes one of the domains and kills the other one. When the live migration enters its last phase, qemu pauses the domain and transfers the rest of its state. And it stays paused until libvirtd starts and notices that the domain is paused for migration couldn't successfully finish without libvirtd and resumes it. IMHO the only way to fix this is to route migration data through libvirt so that if libvirtd crashes or is stopped, the migration is automatically canceled since qemu will not be able to send migration data. Actually, there might be another solution. Qemu could be patched to cancel migration in case the monitor connection that requested it is closed. But I have no idea how feasible this is. This is not an issue in practice since a crashed libvirtd will be followed by its restart (systemd restarts the daemon automatically and so does RHEV on RHEL-6 via upstart) and libvirtd will cancel the migration when it starts. I think there's no need to spend time on this bug. |