[Pacemaker] One more globally-unique clone question

[Andrew Beekhof]

> On 20 Jan 2015, at 4:13 pm, Vladislav Bogdanov <bubble at hoster-ok.com> wrote:
> 
> 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.

Are they allocated in stages though?
Ie. Was there a point at which the "mother-node" was available but constraints prevented broker-vips:1 running there?

> 
>> 
>> Getting them to auto-rebalance is the harder problem
> 
> I see. Should it be possible to solve it without priority or utilization use?

"it" meaning auto-rebalancing or your original issue?

> 
>> 
>>> 
>>> 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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> 
> 
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