First you will download the new software and locate it alongside the current software on each node. Next you will step through the component upgrade sequence, stopping each associated process, switching to the new software version, and restarting the process.
You’ll use the hdp-select
script to switch software versions. The script is
included in the HDP repo, and requires root permissions. hdp-select
sets up
symlinks to hdp-current
and modifies paths for configuration directories.
After each component upgrade you’ll validate the results. When all components are running on the new software, check that your cluster is running to your satisfaction before finalizing the upgrade.
Although the rolling upgrade process minimizes service disruptions, the following components require service disruption during their portion of the rolling upgrade process:
Falcon server
Knox server
Storm (Storm workloads will run during HDFS, YARN, HBase, and Hive upgrades)
Storm on YARN via Slider
Slider apps
Hue server
Accumulo
Where applicable, this is noted in the upgrade and downgrade instructions.