To start Cassandra locally, execute the Cassandra script. If no arguments are passed, it will run in the foreground. To have it run in the background, send the -p flag with a destination file for the Process ID (PID):
cd cassandra
bin/cassandra -p cassandra.pid
This will store the PID of the Cassandra process in a file named cassandra.pid in the local/cassandra directory. Several messages will be dumped to the screen. The node is successfully running when you see this message:
Starting listening for CQL clients on localhost/192.168.0.101:9042 (unencrypted).
This can also be verified with the nodetool status command:
bin/nodetool status
Datacenter: ClockworkAngels
===========================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Address Load Tokens Owns (effective) Host ID Rack
UN 192.168.0.101 71.26 KiB 24 100.0% 0edb5efa... R40