[pve-devel] successfull migration but failed resume

[Alexandre DERUMIER]

>>But isn't it a simple rename right now? Under which circumstances this can fail? 
Yes, it's just a rename, chance to fail are very little.

A host crash between the end of the migration and the rename file can give us problem for example.



----- Mail original ----- 

De: "Stefan Priebe - Profihost AG" <s.priebe at profihost.ag> 
À: "Alexandre DERUMIER" <aderumier at odiso.com> 
Cc: "Dietmar Maurer" <dietmar at proxmox.com>, pve-devel at pve.proxmox.com 
Envoyé: Samedi 23 Février 2013 09:29:00 
Objet: Re: [pve-devel] successfull migration but failed resume 

But isn't it a simple rename right now? Under which circumstances this can fail? 

Am 23.02.2013 um 08:05 schrieb Alexandre DERUMIER <aderumier at odiso.com>: 

>>> yes 
> 
> Well, No really, 
> 
> if the migration fail, the target vm process is always killed, so it's not a problem. 
> 
> The problem is when we have the target vm correctly migrated, but the vm config file that is keep on first node.(timeframe windows is very short,maybe 1s) 
> In this case,you have a "phantom" kvm process on target, as user don't see the vm on target node, and user can start again the vm on first node, and boom. 
> 
> 
> 
> It was really a problem last year, If I remember the vm config file was moved at the begin of the migration, and we killed the sourcevm when migration failed. 
> But killing the sourcevm didn't always working,so we had a "phantom" process on sourcevm and user can start again the vm on target vm and boom. 
> 
> 
> So this is why we start in paused. But the risk currently is in the little timeframe at the end of the migration, when we need to move the config file. 
> 
> Ideas are welcome to improve this ;) 
> 
> 
> 
> 
> 
> ----- Mail original ----- 
> 
> De: "Dietmar Maurer" <dietmar at proxmox.com> 
> À: "Stefan Priebe - Profihost AG" <s.priebe at profihost.ag> 
> Cc: "Alexandre DERUMIER" <aderumier at odiso.com>, pve-devel at pve.proxmox.com 
> Envoyé: Vendredi 22 Février 2013 20:04:37 
> Objet: RE: [pve-devel] successfull migration but failed resume 
> 
>> Mhm but in cases like Mine we have no running vm on both sides. So are you 
>> sure that when migrating there could be a reason to have two vms running? 
> 
> yes