I have to do the same as before: change the “category” on a whole bunch of nodes.
NB the Developer Manual has some typos, where it makes it look like you can specify categories as strings of their names, e.g. cluster.get_by_type('Node')
Cluster means different things to different people. In the context of this article, cluster is best defined as scale-out -- scale-out clusters generally have a lot of the same type of components like Web farms, render farms, and high performance computing (HPC) systems. Administrators will tell you that with scale-out clusters any change, no matter how small, must be repeated up to hundreds of thousands of times; the laziest of admins have mastered techniques of scale-out management so that regardless of the number of nodes, the effort is the same. In this article, the authors peer into the minds of the laziest Linux® admins on Earth and divulge their secrets.