If you have used Cloudera Manager to install Impala, then you can use the Cloudera Manager UI to start/shutdown Impala. However, those who installed Impala directly need to start at least one instance of Impala-state-store and Impala on all DataNodes where it is installed. In this scenario, you can either use init scripts or you can start the statestore and Impala directly. Impala uses Impala-state-store to run in the distributed mode. Impala-state-store helps Impala to achieve the best performance; however, if the state store becomes unavailable, Impala continues to function.

To start the Impala-state-store, use the following command:

$ sudo service impala-state-store start

To start Impala on each DataNode, use the following command:

$ sudo service impala-server start

Impala-state-store and Impala server-specific init scripts are located at /etc/default/impala, which can be edited if necessary when you want to automate or start these services depending on certain conditions.