[Openstack] [nova] [cinder] Nova-volume vs. Cinder in Folsom

Huang Zhiteng winston.d at gmail.com
Wed Jul 11 15:49:46 UTC 2012


+1 for Option 1.

On Wed, Jul 11, 2012 at 11:26 PM, Vishvananda Ishaya
<vishvananda at gmail.com> wrote:
> Hello Everyone,
>
> Now that the PPB has decided to promote Cinder to core for the Folsom
> release, we need to decide what happens to the existing Nova Volume
> code. As far as I can see it there are two basic strategies. I'm going
> to give an overview of each here:
>
> Option 1 -- Remove Nova Volume
> ==============================
>
> Process
> -------
>  * Remove all nova-volume code from the nova project
>  * Leave the existing nova-volume database upgrades and tables in
>    place for Folsom to allow for migration
>  * Provide a simple script in cinder to copy data from the nova
>    database to the cinder database (The schema for the tables in
>    cinder are equivalent to the current nova tables)
>  * Work with package maintainers to provide a package based upgrade
>    from nova-volume packages to cinder packages
>  * Remove the db tables immediately after Folsom
>
> Disadvantages
> -------------
>  * Forces deployments to go through the process of migrating to cinder
>    if they want to use volumes in the Folsom release
>
> Option 2 -- Deprecate Nova Volume
> =================================
>
> Process
> -------
>  * Mark the nova-volume code deprecated but leave it in the project
>    for the folsom release
>  * Provide a migration path at folsom
>  * Backport bugfixes to nova-volume throughout the G-cycle
>  * Provide a second migration path at G
>  * Package maintainers can decide when to migrate to cinder
>
> Disadvantages
> -------------
>  * Extra maintenance effort
>  * More confusion about storage in openstack
>  * More complicated upgrade paths need to be supported
>
> Personally I think Option 1 is a much more manageable strategy because
> the volume code doesn't get a whole lot of attention. I want to keep
> things simple and clean with one deployment strategy. My opinion is that
> if we choose option 2 we will be sacrificing significant feature
> development in G in order to continue to maintain nova-volume for another
> release.
>
> But we really need to know if this is going to cause major pain to existing
> deployments out there. If it causes a bad experience for deployers we
> need to take our medicine and go with option 2. Keep in mind that it
> shouldn't make any difference to end users whether cinder or nova-volume
> is being used. The current nova-client can use either one.
>
> Vish
>
>
> _______________________________________________
> Mailing list: https://launchpad.net/~openstack
> Post to     : openstack at lists.launchpad.net
> Unsubscribe : https://launchpad.net/~openstack
> More help   : https://help.launchpad.net/ListHelp



-- 
Regards
Huang Zhiteng




More information about the Openstack mailing list