Several Flume components support SSL, but they all have their own config parameters for specifying the location and password for keystore and truststore.
These parameters could be passed as standard JSSE system properties (specified in flume-env.sh):
This would be a more consistent and standard based configuration.
Specifying passwords in system properties means that the passwords can be seen in the process list. For cases where it is not acceptable, it will also be possible to define the parameters in environment variables.
The logic of applying the SSL config parameters for an SSL-enabled source/sink:
- if the agent config defines the SSL parameter for the component, then they will be used (allowing customisation and backward compatibility)
- if no SSL parameters are defined for the component, but the -D system properties are present, then they will be used
- if neither the component SSL parameters nor the -D system properties are defined, but the environment variable are present, then they will be used
- otherwise config error
So the priority:
- component parameters in agent config
- -D system properties
- environment variables