3.1. Simplify administration using a cluster shell
In the dark past, configuring Pacemaker required the administrator to read and write XML. In true UNIX style, there were also a number of different commands that specialized in different aspects of querying and updating the cluster.
All of that has been greatly simplified with the creation of unified command-line shells (and GUIs) that hide all the messy XML scaffolding.
These shells take all the individual aspects required for managing and configuring a cluster, and pack them into one simple-to-use command line tool.
They even allow you to queue up several changes at once and commit them all at once.
Two popular command-line shells are pcs and crmsh. Clusters from Scratch is based on pcs because it comes with CentOS, but both have similar functionality. Choosing a shell or GUI is a matter of personal preference and what comes with (and perhaps is supported by) your choice of operating system.
