Open Stack

On 6/15/2016 10:30 AM, Daniel P. Berrange wrote:
> On Wed, Jun 15, 2016 at 03:19:28PM +0000, Jesse Keating wrote:
>> I'll offer a counter point.
>>
>> We're not doing Juno to Mitaka, however we are doing Kilo to Mitaka, skipping
>> over Liberty.
>>
>> The database migrations to get from Kilo to Mitaka have ran smoothly for us.
>
> While it is great that it /appeared/ to work correctly for you, that is in
> no way guaranteed. There also might be data that has silently been incorrectly
> migrated due to missing the intermediate release that could cause problems
> at some indeterminate point down the road. While we do test the N -> N+1
> upgrade path, there is no CI testing of the N -> N + 2 upgrade path. IOW
> while it may have worked for you between these 2 particular releases, there
> is again no guarantee it'll work for any future pair of N, N+2 releases.
> If you want to accept the risks, that's fine, but I'd certainly not suggest
> it is a reasonable thing todo for deployments in general. Also what happened
> to work for you may just as easily not work for other people, depending on
> characteristics of their deployment configuration & data set.
>
> Regards,
> Daniel
>

+1 to everything Daniel said. Nova really expects release-to-release 
upgrades. We do online data migrations between releases. Maybe one 
reason you're getting this to work is we have a nova-manage command to 
force the migration of data between releases rather than doing the 
online data migration as resources are accessed. But there are some DB 
migrations where we do a full stop until you've migrated the data.

-- 

Thanks,

Matt Riedemann