Patching Amazon EMR¶
Rackspace’s recommended method for securing EMR clusters with current software updates is to launch a new EMR cluster, using the latest EMR release. EMR clusters are not intended for indefinite runtime and are expected to terminate after a specific processing job (Transient clusters) or after a succession of jobs (Long-running clusters).
Note: If an EMR cluster is using a custom AMI, a new AMI should be created including the desired updates, and a new EMR cluster launched with the new AMI (the AMI used for an EMR cluster cannot be altered after launch).
It is possible to manually patch cluster instances in-place using OS management access to the instances. This may be appropriate if an EMR cluster needs to remain provisioned for a recurring job, but security updates are critical. The EMR cluster should be replaced using the recommended method above as soon as a downtime window is available.
Note: Any new instances that are launched - either through scaling changes or self-healing - will apply outstanding patches at launch.