Docker known issues

The following issues are recognized.

• Cassandra File System (CFS) is not supported.
• Lifecycle Manager (LCM) is not supported.
• Changing any file not included in the list of approved configuration files will require an additional host volume or customization of the image. An example is SSL key management.
• The JVM heap size must be set for DataStax Enterprise (DSE) running inside the container using the JVM_EXTRA_OPTS variable or custom cassandra-env.sh. If not set, Java does not honor resource limits set for the container, and will peer through the container to use resources (memory and CPU) of the host. See the JVM_EXTRA_OPTS variable in Using environment variables for more information.