Performing a Rolling Upgrade on a CDH 5 Cluster
The rolling upgrade feature takes advantage of parcels and the HDFS high availability to enable you to upgrade your cluster software and restart the upgraded services without taking the entire cluster down. You must have HDFS high availability enabled to perform a rolling upgrade.
This page described how to perform a rolling upgrade between maintenance and minor versions of CDH 5, except Beta versions. For rolling upgrade between CDH 4 versions, see Performing a Rolling Upgrade on a CDH 4 Cluster.
It is not possible to perform a rolling upgrade from CDH 4 to CDH 5 because of incompatibilities between the two major versions. Instead, follow the instructions for a full upgrade at Upgrading from CDH 4 to CDH 5 Parcels.