Bug 1291569

Summary:	Live merge: Engine must refresh resized volume on HSM prior to starting merge
Product:	[oVirt] ovirt-engine	Reporter:	Tal Nisan <tnisan>
Component:	BLL.Storage	Assignee:	Allon Mureinik <amureini>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Aharon Canan <acanan>
Severity:	high	Docs Contact:
Priority:	unspecified
Version:	3.6.0	CC:	acanan, alitke, amureini, bugs, gpadgett, tnisan, ylavi
Target Milestone:	ovirt-3.6.2	Flags:	rule-engine: ovirt-3.6.z+ ylavi: planning_ack+ tnisan: devel_ack+ acanan: testing_ack+
Target Release:	3.6.2
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:	1274323	Environment:
Last Closed:	2016-02-18 11:19:51 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	Storage	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1274323, 1292129
Bug Blocks:	1232481

Description Tal Nisan 2015-12-15 08:11:22 UTC

+++ This bug was initially created as a clone of Bug #1274323 +++

Description of problem:

If a drive was enlarged after creation of a snapshot then the volume associated with the snapshot will be smaller than the currently active volume.  If the snapshot volume is also on preallocated block storage then engine needs to manually enlarge the snapshot volume prior to starting a live merge.

Today, engine issues the extendVolumeSize call to SPM but it does not notify the host running the VM (HSM host) that the volume has been resized.  This means that when a VM is running on a non-SPM host the resize won't be picked up by qemu and the merge will fail.


Version-Release number of selected component (if applicable):
ovirt-engine-4.0.0-0.0.master.20151020161541.git37557f3.el7.centos.noarch

How reproducible:
Always

Steps to Reproduce:
1. Start a VM on a non-SPM host with a preallocated block disk
2. Create a snapshot involving the disk
3. Enlarge the disk by 1GB
4. Delete the snapshot

Actual results:
The merge fails with an error like the following on the HSM host:

libvirtError: internal error: unable to execute QEMU command 'block-commit': Top image /rhev/data-center/108151fa-1c40-4ee3-bae0-d91d0e56f44d/2276ca67-cdff-4bde-b437-446fc2e92a46/images/65ade35f-deed-4e0d-8a73-7c98c80fb661/b97c3c80-f781-4b51-bb79-5929fd9f3cf8 is larger than base image /rhev/data-center/108151fa-1c40-4ee3-bae0-d91d0e56f44d/2276ca67-cdff-4bde-b437-446fc2e92a46/images/65ade35f-deed-4e0d-8a73-7c98c80fb661/71bc1e19-e392-4121-9c2f-896d7402db22, and resize of base image failed: Invalid argument

Expected results:

The snapshot should be removed successfully.

Additional info:

--- Additional comment from Adam Litke on 2015-10-22 16:36 IDT ---



--- Additional comment from Adam Litke on 2015-10-22 16:37 IDT ---



--- Additional comment from Adam Litke on 2015-10-22 16:37 IDT ---



--- Additional comment from Adam Litke on 2015-10-22 16:38:46 IDT ---

I believe the proper way to fix this is for engine to issue a diskSizeExtend to the HSM host as discussed in the Feature Page for online disk resize:

http://www.ovirt.org/Features/Online_Virtual_Drive_Resize#Detailed_Description

--- Additional comment from Yaniv Dary on 2015-10-29 14:51:23 IST ---

In oVirt testing is done on single release by default. Therefore I'm removing the 4.0 flag. If you think this bug must be tested in 4.0 as well, please re-add the flag. Please note we might not have testing resources to handle the 4.0 clone.

Comment 1 Red Hat Bugzilla Rules Engine 2015-12-15 08:11:26 UTC

Bug tickets must have version flags set prior to targeting them to a release. Please ask maintainer to set the correct version flags and only then set the target milestone.

Comment 2 Sandro Bonazzola 2015-12-23 13:43:52 UTC

oVirt 3.6.2 RC1 has been released for testing, moving to ON_QA

Comment 3 Aharon Canan 2015-12-29 11:53:22 UTC

Verified using the following versions:
---------------------------------------
rhevm-3.6.2-0.1.el6.noarch - running on Rhel6.7
vdsm-4.17.14-0.el7ev.noarch - running on Rhel7.2

Scenario 1:
----------------
1. Create a VM with 1gb preallocated disk on a block-based domain.
2. Create a snapshot.
3. Extend the disk to 2gb.
4. Start the VM on HSM.
5. Delete the snapshot