[ClusterLabs] About Corosync up to 16 nodes limit

[Digimer]

On 2017-07-05 09:03 PM, mlb_1 wrote:
> Hi:
>       I heard corosync-node's number limit to 16？ It's true？ And Why?
>      Thanks for anyone's answer.
> 
>    
>  https://specs.openstack.org/openstack/fuel-specs/specs/6.0/pacemaker-improvements.html 
>     
> 
>   * Corosync 2.0 has a lot of improvements that allow to have up to 100
>     Controllers. Corosync 1.0 scales up to 10-16 node

There is no hard limit on how many nodes can be in a cluster, but Red
Hat supports up to 16. SUSE supports up to 32, iirc. The problem is that
it gets harder and harder to keep things stable as the number of nodes
grow. There is a lot of coordination that has to happen between the
nodes and it gets ever more complex.

Generally speaking, you don't want large clusters. It is always advised
to break things up it separate smaller clusters whenever possible.


-- 
Digimer
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