Open Stack

On 10/31/2017 01:13 AM, haad wrote:
> Hi,
>
> We have an OSA installation with 10-12 compute nodes running Mitaka on Ubuntu
> 16.04. As initially we have not prepared any long term update strategy we would
> like to create one now. Plan would be to upgrade it to new OSA
> release(Ocata/Pike/Queens) in near future.
>
> Our original plan was to update management/networking/backend at once by using
> rolling updates to newer release and then upgrade compute nodes one by one to
> new release.. I think that [2] provides a general upgrade manual. Is there any
> document describing how are different OSA releases compatible ? Is there any
> policy in place about backward compatibility ?

As a general rule, OpenStack only supports an online upgrade of one version at a 
time.  That is, controller nodes running version N can talk to compute nodes 
running version N-1.

If you can tolerate downtime of the API layer, there has been some discussion 
around "skip-level" upgrades.

Chris