[ovirt-users] oVirt VM backup and restore

[Juan Hernández]

On 03/09/2017 10:25 AM, Gianluca Cecchi wrote:
> On Wed, Mar 8, 2017 at 6:05 PM, Gianluca Cecchi
> <gianluca.cecchi at gmail.com <mailto:gianluca.cecchi at gmail.com>> wrote:
> 
> 
> 
>     NOTE: during the snapshot creation I see in web admin console the VM
>     in paused state and also not responsive in both console and ssh session.
>     After a couple of seconds it comes back and as a confirmation I see
>     this in its messages:
> 
>     Mar  8 17:38:57 T-ORACLE73 chronyd[616]: System clock wrong by
>     19.077230 seconds, adjustment started
> 
>     Is this expected?
> 
> 
> 
> 
> Possibly the default changed at some point in time, so that now it saves
> memory and so this implies pause of VM
> 
> In the mean time I verified changing backup.py this way solves the
> problem (the 3.6 api deprecation still in place... ;-):
> 
> $ diff backup.py backup.py.orig 
> 123c123
> <                    
> vm.snapshots.add(params.Snapshot(description=config.get_snapshot_description(),
> vm=vm,persist_memorystate=False))
> ---
>>                    
> vm.snapshots.add(params.Snapshot(description=config.get_snapshot_description(),
> vm=vm))
> 
> The snapshot doesn't include memory and no problem at VM OS side now
> 
> Tested also getting the parameter from config file
> 
> Modifications needed in this case:
> 
> 1)
> $ diff backup.py backup.py.orig 
> 123c123
> <                    
> vm.snapshots.add(params.Snapshot(description=config.get_snapshot_description(),
> vm=vm,persist_memorystate=config.get_persist_memorystate()))
> ---
>>                    
> vm.snapshots.add(params.Snapshot(description=config.get_snapshot_description(),
> vm=vm))
> 
> 
> 2)
> $ diff config.py config.py.orig 
> 34d33
> <             self.__persist_memorystate =
> config_parser.getboolean(section, "persist_memorystate")
> 113,116d111
> < 
> < 
> <     def get_persist_memorystate(self):
> <         return self.__persist_memorystate
> 
> 
> And in config file called add:
> 
> # Save Memory in snapshot
> persist_memorystate=False
> 
> It could be further improved if one wants to differentiate save memory
> for some VMs and not for other ones....
> 
> HIH other ones,
> Gianluca
> 

Very good point Gialuca, you are right, the 'persist_memorystate' flag
is 'true' by default, and that makes the pause longer. Would you be so
kind to add it to the 'vm_backup.py' example that is part of version 4
of the SDK?


https://github.com/oVirt/ovirt-engine-sdk/blob/master/sdk/examples/vm_backup.py#L143-L151

(Note that that Gibhub is just a mirror, the change needs to be submited
using gerrit.ovirt.org).