openstack team mailing list archive

[Aniruddha Khadkikar <askhadkikar@xxxxxxxxx>]

On Sat, Nov 3, 2012 at 9:06 PM, Tim Bell <Tim.Bell@xxxxxxx> wrote:
>
> Puppet is great for this sort of thing. There are various ways of querying
> parameters and making choices about them. A typical example would be where
> you want to adjust a configuration parameter due to memory configuration or
> network.

I managed to get an overview of Puppet's approach. I agree that Puppet
is great for configuration management. In your experience how is the
change in Nova configuration parameters from Essex to Folsom dealt
with? Is Puppet being configured so that all known configurable
parameters for Nova are documented in a custom fact collector?
In our lab deployment our conf files only contain those parameters
that we want to define and we're happy to work with defaults for the
rest. It appears our approach may be incorrect as we're destroying the
source data which Facter can mine.

>
> Writing the puppet configuration is not difficult... Puppetlabs have an
> excellent and actively maintained configuration suite on the puppetforge for
> OpenStack along with tutorial videos.
>
> Chef support is also there so there is choice. The DevOps panel gives some
> discussion around this
> (http://www.openstack.org/summit/san-diego-2012/openstack-summit-sessions/pr
> esentation/devops-panel)
>
> I think building an openstack specific database for configuration would be
> hard work to include all of the flexibility that Puppet offers.  It is worth
> having a good look at puppet or chef before starting this.
>

Tim - I totally am with you on this. It will definitely be a rethink
and lot of hard work! My intention is not to replicate Puppet's
functiionality. It's on how to manage the Openstack 'data dictionary'
in a simpler way than a large number of conf files. I am trying to
visualize what difficulties we would face in operations, especially
doing change management for successive releases of Openstack which
might contain changes in the number and type of configurable
parameters and possibly changes in the default values.

> Tim
>
>>
>> @Jon - I am happy that these ideas resonate with you. My moot point is
> that
>> the metadata should be within the openstack implementation and not
> outside.
>> I am not very familiar with Puppet - is there a way to query the
> parameters set
>> in the conf file. I would think that Puppet would be given a conf file to
> deploy.
>> The values within the conf file would still remain abstracted and not be
> readily
>> available. Please correct me if I'm wrong in my presumption. Having the
>> parameters with their default values in the data store would allow a
> better
>> understanding of the different configuration parameters. Also if its in a
>> database then dependency and relationship rules or even constraints
>> (permissible values) could be defined.
>>