controlled shutdown

Hi,

In this link https://cwiki.apache.org/confluence/display/KAFKA/Replication+tools
two ways to do controlled shutdown are mentioned. "The first approach is to set
"controlled.shutdown.enable" to true in the broker. Then, the broker will try to
move all leaders on it to other brokers one at time before shutting itself down"

For this approach, what is the expected way to shut down the broker? Kill the
process or send a signal? Thanks.

Libo