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5.4. Prevent Resources from Moving after Recovery

In most circumstances, it is highly desirable to prevent healthy resources from being moved around the cluster. Moving resources almost always requires a period of downtime. For complex services such as databases, this period can be quite long.
To address this, Pacemaker has the concept of resource stickiness, which controls how strongly a service prefers to stay running where it is. You may like to think of it as the "cost" of any downtime. By default, Pacemaker assumes there is zero cost associated with moving resources and will do so to achieve "optimal" [12] resource placement. We can specify a different stickiness for every resource, but it is often sufficient to change the default.
[root@pcmk-1 ~]# pcs resource defaults resource-stickiness=100
[root@pcmk-1 ~]# pcs resource defaults
resource-stickiness: 100

Note

Earlier versions of pcs, such as the one shipped with Fedora 20, require that rsc be added after resource in the above commands.


[12] Pacemaker’s definition of optimal may not always agree with that of a human’s. The order in which Pacemaker processes lists of resources and nodes creates implicit preferences in situations where the administrator has not explicitly specified them.