Bug 1042706

Summary: qemu should provide error msg when migration from a newer host to an older.
Product: Red Hat Enterprise Linux 7 Reporter: zhe peng <zpeng>
Component: qemu-kvmAssignee: Hai Huang <hhuang>
Status: CLOSED WONTFIX QA Contact: Virtualization Bugs <virt-bugs>
Severity: medium Docs Contact:
Priority: medium    
Version: 7.0CC: acathrow, dyuan, hhuang, jdenemar, juzhang, mzhan, qzhang, virt-maint, xfu, ydu
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2014-01-07 13:08:54 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description zhe peng 2013-12-13 06:36:34 UTC 
Description
libvirt should fail migration and provide error msg when migration from a newer host to an older.

Version:
rhel6.5:libvirt-0.10.2-29.el6_5.2.x86_64
rhel7.0:libvirt-1.1.1-14.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1:prepare two host,on with rhel6.5, the other is rhel7.0
2:prepare a healthy guest on rhel6.5 host
3:migrate the guest to rhel7.0, it can worked well.
4:migrate the guest back to rhel6.5
# virsh migrate --live rhel6 qemu+ssh://10.66.84.16/system --verbose
root.84.16's password:
Migration: [100 %]

it seems worked, but actually, qemu-kvm can't support this, after migration, the guest can't be used.
so libvirt should forbid this action, and provide some error msg to customer.


Actual results：


Expected results:


Additional info:
Comment 2 Jiri Denemark 2013-12-13 09:57:55 UTC 
Knowing what versions of qemu-kvm are able to migrate between each other is not a libvirt's business. I'm moving this bug to QEMU for investigating why the guest doesn't work after migration while migration seems to have succeeded.
Comment 3 juzhang 2013-12-13 10:04:31 UTC 
FYI

Bug 1027572 - [RFE]should support migration from RHEL7.0 host to RHEL6.5 host(CLOSED WONTFIX )