Open Stack

On 02/05/2016 04:44 AM, Grasza, Grzegorz wrote:
> 
> 
>> -----Original Message-----
>> From: Sean Dague [mailto:sean at dague.net]
>>
>> On 02/04/2016 10:25 AM, Grasza, Grzegorz wrote:
>>>
>>> Keystone is just one service, but we want to run a test, in which it
>>> is setup in HA – two services running at different versions, using the same
>> DB.
>>
>> Let me understand the scenario correctly.
>>
>> There would be Keystone Liberty and Keystone Mitaka, both talking to a
>> Liberty DB?
>>
> 
> The DB would be upgraded to Mitaka. From Mitaka onwards, we are making only additive schema changes, so that both versions can work simultaneously.
> 
> Here are the specifics:
> http://docs.openstack.org/developer/keystone/developing.html#online-migration

Breaking this down, it seems like there is a simpler test setup here.

Master keystone is already tested with master db, all over the place. In
unit tests all the dsvm jobs. So we can assume pretty hard that that works.

Keystone doesn't cross talk to itself (as there are no workers), so I
don't think there is anything to test there.

Keystone stable working with master db seems like an interesting bit,
are there already tests for that?

Also, is there any time where you'd get data from Keystone new use it in
a server, and then send it back to Keystone old, and have a validation
issue? That seems easier to trigger edge cases at a lower level. Like an
extra attribute is in a payload in Keystone new, and Keystone old
faceplants with it.

The reality is that standing up an HA Proxy Keystone multinode
environment is going to be pretty extensive amount of work. And when
things fail, digging out why, is kind of hard. However it feels like
most of the interesting edges can be tested well at a lower level. And
is at least worth getting those sorted before biting off the bigger thing.

	-Sean

-- 
Sean Dague
http://dague.net