Starting, Stopping, and Restarting Livy
Before you start, stop, or restart Livy, you must perform the following steps:
- Switch user to - livy:- su livy 
- Livy runs by default on port - 8998. Verify that- host:8998is available. You can use lsof to verify the port's availability:- lsof -i 8998 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME java 16358 sam 130u 0x47d85f2c7104d1cd 0t1 TCP *:8998 (LISTEN) 
Follow this step to start the Livy server:
/usr/hdp/<hdp_version>/livy/bin/livy-server start
To verify that the Livy server is running, access the Livy menu in a browser window; for example:
http://<livy-hostname>:8998
Follow this step to stop the Livy server:
/usr/hdp/<hdp_version>/livy/bin/livy-server stop
There is no specific command to restart Livy. To restart Livy, you must first stop Livy, and then start it again.

