Enable SSL for Impala

Impala 2.5.0 supports SSL encryption for internal Impala connections.

Complete the following steps to configure SSL for Impala:

Configure encryption in Hive. See Hive Encryption.
Configure client-server encryption only or configure client-server and Impala internal encryption.
- To configure client-server encryption only, add the following start-up options for the Impala Server to /opt/mapr/impala/impala-<version>/conf/env.sh:
  
  -ssl_server_certificate
  
  Full path to the server certificate on the local filesystem.
  
  -ssl_private_key
  
  Full path to the server private key on the local filesystem.
- To configure client-server and Impala internal encryption, add the following start-up options for the Impala server, catalog, and statestore to /opt/mapr/impala/impala-<version>/conf/env.sh:
  
  -ssl_server_certificate
  
  Full path to the server certificate on the local filesystem.
  
  -ssl_private_key
  
  Full path to the server private key on the local filesystem.
  
  -ssl_client_ca_certificate
  
  Full path to the certificate on the local filesystem required for client/server encryption.

Note: When you add the SSL flags to Impala start-up options, Impala listens for HiveServer2 on the SSL-secured ports. A client program usually has equivalent options to verify a connection to the correct server.

After you enable SSL, you can issue the following options when you start the impala-shell:

Option	Description
`--ssl`	Enables SSL for the impala-shell.
`--ca_cert`	Local path name that points to the third-party CA certificate, or to a copy of the server certificate for self-signed server certificates. If --ca_cert is not set, impala-shell enables SSL, but does not validate the server certificate. This is useful for connecting to an Impala node that you know is only running over SSL when a copy of the certificate is not available.

For more information about the impala-shell, refer to Impala-Shell Commands.

For more information about configuring Impala start-up options, see Additional Impala Configuration Options.