[ClusterLabs] Maintenance mode status in CIB

[Jehan-Guillaume de Rorthais]

On Mon, 12 Oct 2020 19:08:39 -0400
Digimer <lists at alteeve.ca> wrote:

> Hi all,

Hi you,

> 
>   I noticed that there appear to be a global "maintenance mode"
> attribute under cluster_property_set. This seems to be independent of
> node maintenance mode. It seemed to not change even when using
> 'pcs node maintenance --all'

You can set maintenance-mode using:

  pcs property set maintenance-mode=true

You can read about "maintenance-mode" cluster attribute and "maintenance" node
attribute in chapters:

  https://clusterlabs.org/pacemaker/doc/en-US/Pacemaker/2.0/html/Pacemaker_Explained/s-cluster-options.html 
  https://clusterlabs.org/pacemaker/doc/en-US/Pacemaker/2.0/html/Pacemaker_Explained/_special_node_attributes.html

I would bet the difference is that "maintenance-mode" applies to all nodes in
one single action. Using 'pcs node maintenance --all', each pcsd daemon apply
the local node maintenance independently. 

With the later, I suppose you might have some lag between nodes to actually
start the maintenance, depending on external factors. Moreover, you can
start/exit the maintenance mode independently on each nodes.