← Back to team overview

openstack team mailing list archive

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

 

+1 to option 1, rip the band-aid off quickly  :-)

-Doug

> -----Original Message-----
> From: openstack-bounces+gregory_althaus=dell.com@xxxxxxxxxxxxxxxxxxx
> [mailto:openstack-bounces+gregory_althaus=dell.com@lists.launchpad.
> net] On Behalf Of Vishvananda Ishaya
> Sent: Wednesday, July 11, 2012 10:27 AM
> To: Openstack (openstack@xxxxxxxxxxxxxxxxxxx) 
(openstack@xxxxxxxxxxxxxxxxxxx)
> Subject: [Openstack] [nova] [cinder] Nova-volume vs. Cinder in Folsom
> 
> 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@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~openstack
> More help   : https://help.launchpad.net/ListHelp

References