When we talk about provisioning clusters, it means that we have to store and share the status of resources between different instances.
We name the node as an instance member of the provisioning cluster.
We can see two approaches to share the status of the resources.
The first approach is to use a central component to store the status. This central component is named cluster manager
. It's responsible for storing the data shared between the nodes and the communication between the nodes. Have a look at the following diagram:
![](https://static.packt-cdn.com/products/9781783984602/graphics/4602OS_02_01.jpg)
All nodes are connected to a central component storing the status of the resources. For instance, this component could be Apache ZooKeeper.
The advantage of this approach is that the provisioning cluster has no impact on the nodes; a node just communicates with the central component.
The cluster manager is not just a simple shared storage, as it has to deal with the communication and transport of information between the nodes.
A drawback of this approach is...