Before starting the upgrade process, collect information about the topology of your cluster: the components, master processes, slave processes, and clients running on each node.
You will need root, administrative, or root-equivalent authorization to run
hdp-select on all servers in the cluster, and superuser access to access and
upgrade components.
On every node, make sure that the /usr directory can hold the new version of
software in addition to your current version. Plan on 2.5 GB per version for an installation
with all components.
The cluster will use your existing 2.2 locations for data and log files.
If you wish to add components to your cluster, complete the rolling upgrade process before adding the new components.
