[node-devel] CIM plugin for oVirt Node

[Anthony Liguori]

On 01/30/2012 08:59 AM, Charles_Rose at dell.com wrote:
>
>
> On Monday 30 January 2012 08:12 PM, Perry Myers wrote:
>> On 01/30/2012 08:45 AM, Daniel Veillard wrote:
>>>    Hi everybody,
>>>
>>> I guess the best is to ask Chip Vincent about those oVirt Node
>>> integration issues. CIM is not always trivial to setup in a normal
>>> RHEL environment, and I'm afraid nobody tried it on a read-only
>>> root/stateless environment. Chip I think the expertise from some
>>> of your libvirt-cim team is needed there, I guess the best is to provide
>>> an image to someone knowledgeable in the set-u and have him check
>>> the issues. Maybe Eduardo ro you can have a look ?
>>>
>>>    thanks !
>>>
>>> Daniel
>>>
>>> On Sun, Jan 29, 2012 at 10:39:03AM -0500, Perry Myers wrote:
>>>> One of the items on our backlog has been to include CIM server/providers
>>>> on oVirt Node.  Initially we'll do this statically and include things
>>>> like sblim, tog-pegasus, libvirt-cim as part of the core Node recipe.
>>>
>>> P.S.: shouldn't only one of sblim/tog-pegasus be needed and not both ?
>>>        One server should be sufficient isn't it and the goal is still
>>>        to limit the size of images. Which one to pick may be the result
>>>        of which one is the easier to coerce to work in root RO mode,
>>>        or the smaller of the two ...
>>
>> I asked Anthony about this, and he explained it to me...  sblim is both
>> a collection of CIM providers as well as a server.  tog-pegasus is just
>> the server.
>>
>> So you can either use:
>> sblim + tog-pegasus
>> or
>> sblim + sblim-sfcb
>>
>> If you omit sfcb from the oVirt Node, then you can use tog-pegasus in
>> its place.  It's also my understanding that sblim-sfcb and tog-pegasus
>> are not fully interchangeable as there are some providers that will only
>> work with one or the other.  So far, it seems like tog-pegasus is what
>> folks want specifically, so that is what we have been focusing on.
>
> We have had issues with sfcb and tog-pegasus conflicting in the past:
> 	https://bugzilla.redhat.com/show_bug.cgi?id=604578
>
> sblim + sblim-sfcb is what we needed and tog-pegasus was installed as
> part of the @base install.

Let me start out by saying that I know almost nothing about CIM so I'm largely 
talking out of my....

I think the first question to answer is why we're adding CIM to oVirt node in 
the first place.

Is the goal to expose a specific DMTF schema for on-node management?  Is it to 
allow arbitrary third-party CMPI providers to be added for hardware management? 
  Is it to allow third party CIM management suites to see and manage ovirt-node 
instances?

For just about any of these, if the answer isn't qualified with "exclusively for 
use by ovirt-engine", how is a split brain going to be avoided?

I think the provider needs ultimately will determine what cimmon is necessary.

Just to further complicate things, most providers these days are still only 
32-bit as I understand it...

Regards,

Anthony Liguori