[Pacemaker] One more globally-unique clone question

[Vladislav Bogdanov]

20.01.2015 02:47, Andrew Beekhof wrote:
>
>> On 17 Jan 2015, at 1:25 am, Vladislav Bogdanov
>> <bubble at hoster-ok.com> wrote:
>>
>> Hi all,
>>
>> Trying to reproduce problem with early stop of globally-unique
>> clone instances during move to another node I found one more
>> "interesting" problem.
>>
>> Due to the different order of resources in the CIB and extensive
>> use of constraints between other resources (odd number of resources
>> cluster-wide) two CLUSTERIP instances are always allocated to the
>> same node in the new testing cluster.
>
> Ah, so this is why broker-vips:1 was moving.

That are two different 2-node clusters with different order of resources.
In the first one broker-vips go after even number of resources, and one 
instance wants to return to a "mother-node" after it is brought back 
online, thus broker-vips:1 is moving.

In the second one, broker-vips go after odd number of resources 
(actually three more resources are allocated to one node due to 
constraints) and both boker-vips go to another node.

>
>>
>> What would be the best/preferred way to make them run on different
>> nodes by default?
>
> By default they will. I'm assuming its the constraints that are
> preventing this.

I only see that they are allocated similar to any other resources.

>
> Getting them to auto-rebalance is the harder problem

I see. Should it be possible to solve it without priority or utilization 
use?

>
>>
>> I see following options:
>> * Raise priority of globally-unique clone so its instances are
 >> always allocated first of all.
>> * Use utilization attributes (with high values for nodes and low values
>> for cluster resources).
 >> * Anything else?
>>
>> If I configure virtual IPs one-by-one (without clone), I can add a
>> colocation constraint with negative score between them. I do not
>> see a way to scale that setup well though (5-10 IPs). So, what
>> would be the best option to achieve the same with globally-unique
>> cloned resource? May be there should be some internal
>> preference/colocation not to place them together (like default
>> stickiness=1 for clones)? Or even allow special negative colocation
>> constraint and the same resource in both 'what' and 'with'
>> (colocation col1 -1: clone clone)?
>>
>> Best, Vladislav
>>
>>
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>
>
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