[one-users] the synchronous problem between the cancel operation and tm_delete.sh for lxc driver (Users Digest, Vol 58, Issue 20)

[Ruben S. Montero]

Hi guys,

After a brief meeting, it seems clear that we need to introduce the
synchronization point between TM and VMM operations upon vm deletion,
there are several alternatives to implement this that we may want to
refine.....

Anyway, the synchronized delete operation will be implemented for the
next release, it you are interested in tracking this, use [1].

Simon, the ACL option needs changes in the core to move the delete
action to the ADMIN class, so is something that can not be used as a
work around for 3.8.1. I'd say that the recommended workaround is to
introduce the delay in the TM driver (as described by Rolandas) till
this is implemented, if someone is being hit by this...

Thanks for sharing your thoughts on this, very helpful indeed.

Cheers

Ruben

[1] http://dev.opennebula.org/issues/1685

On Fri, Dec 7, 2012 at 2:33 PM, Simon Boulet <simon at nostalgeek.com> wrote:
> Hi,
>
> On Fri, Dec 7, 2012 at 3:13 AM, Rolandas Naujikas
> <rolandas.naujikas at mif.vu.lt> wrote:
>>
>> On 2012-12-06 20:48, Ruben S. Montero wrote:
>>>
>>> Hi
>>>
>>> It seems that this behavior is problematic. Let me elaborate on Simon
>>> comment. As pointed out by Simon there are two similar VM operations:
>>
>>
>> You make more confusion here, because in the past I saw similar problem
>> when developing my own LVM driver. We are talking, that in delete action on
>> VM opennebula executes tm/delete and vmm/cancel actions in parallel what
>> causes problems, because lvm volumes could not be destroyed when in use by
>> xen VM. As a workaround my LVM driver waits in background until it can
>> delete LVM volume.
>
>
> Ruban, shouldn't OpenNebula wait for the VMM cancel to finish before calling
> TM delete in all situations? It's causing me some problem as well. One
> difference between the delete and cancels actions perhaps would be that
> delete doesn't check the return status on the VMM cancel action before
> calling TM delete, because delete is a last case / cleanup action.
>
>
>>>
>>> This seems to be confusing, we are thinking of moving the delete
>>> operation to the ADMIN set (so you need admin permissions to delete)
>>> and so force users to use the safer cancel operation... Any thoughts?
>>
>>
>
> Isn't this already possible using the ACL? Perhaps OpenNebula could ship
> with a default ACL to block some commands from regular users. Do you have a
> sample ACL to block the delete action for regular user?
>
> Thanks!
>
> Simon



-- 
Ruben S. Montero, PhD
Project co-Lead and Chief Architect
OpenNebula - The Open Source Solution for Data Center Virtualization
www.OpenNebula.org | rsmontero at opennebula.org | @OpenNebula