Cassandra example, use nodetool drain in preStop

examples/storage/cassandra/cassandra-statefulset.yaml

@@ -37,7 +37,7 @@ spec:
         lifecycle:
           preStop:
             exec:
-              command: ["/bin/sh", "-c", "PID=$(pidof java) && kill $PID && while ps -p $PID > /dev/null; do sleep 1; done"]
+              command: ["/bin/sh", "-c", "nodetool drain"]
         env:
           - name: MAX_HEAP_SIZE
             value: 512M