Bug 1028768

Summary: [engine-backend] LSM fails due to another operation (attaching the disk snapshot to another VM), which was started after it and managed to take the lock on the disk
Product: Red Hat Enterprise Virtualization Manager Reporter: Elad <ebenahar>
Component: ovirt-engineAssignee: Liron Aravot <laravot>
Status: CLOSED CURRENTRELEASE QA Contact: Elad <ebenahar>
Severity: high Docs Contact:
Priority: unspecified    
Version: 3.3.0CC: abaron, acathrow, amureini, iheim, lpeer, Rhev-m-bugs, scohen, yeylon
Target Milestone: ---Flags: scohen: Triaged+
Target Release: 3.3.0   
Hardware: x86_64   
OS: Unspecified   
Whiteboard: storage
Fixed In Version: is26 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2014-01-21 22:17:04 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:    
Bug Blocks: 922475, 1044030, 1054231    
Attachments:
Description Flags
engine.log none

Description Elad 2013-11-10 15:27:41 UTC
Created attachment 822102 [details]
engine.log

Description of problem:
Live storage migration fails because another operation was managed to take a lock on the disk.
Happened to me when during LSM, I tried to attach the disk snapshot to another VM with REST (as part of the new backup-API feature) 

Version-Release number of selected component (if applicable):
rhevm-3.3.0-0.32.beta1.el6ev.noarch

How reproducible:
100%

Steps to Reproduce:
On a block/file pool with 2 SDs:
1. create 2 VMs with disk and run them 
2. live migrate one of the VMs disk to the second SD
3. during the LSM operation (right after it began), attach the disk snapshot (the one that is simultaneously  migrating) to the other running vm using REST

Actual results:
The disk attachment operation succeeds and LSM fails.

LSM is failing with a CanDoAction:

2013-11-10 15:56:12,613 WARN  [org.ovirt.engine.core.bll.lsm.LiveMigrateVmDisksCommand] (ajp-/127.0.0.1:8702-4) [47722e08] CanDoAction of action LiveMigrateVmDisks failed. Reasons:VAR__ACTION__MOVE,VAR__TYPE__VM_D
ISK,ACTION_TYPE_FAILED_VM_DISK_SNAPSHOT_IS_PLUGGED_TO_ANOTHER_VM,$disksInfo


Expected results:
The migrated disk should be locked until the live storage migration operation ends. Other operations on the same disk should be blocked.

Additional info:
engine.log

Comment 1 Elad 2013-12-15 12:05:43 UTC
When trying to attach a disk snapshot to VM, while the the itself is being live migrated, the operation get blocked by engine, this is the message we get on REST:
[Cannot attach Virtual Machine Disk. Disk iscsi5-3_Disk1 is being moved or copied.]


Verified using is26

Comment 2 Itamar Heim 2014-01-21 22:17:04 UTC
Closing - RHEV 3.3 Released

Comment 3 Itamar Heim 2014-01-21 22:23:42 UTC
Closing - RHEV 3.3 Released