Use the nodetool tool that under the cassandra/bin directory
nodetool status
There are two nodes have been off line.
nodetool removenode 199553f1-f310-41e1-b4a4-f5a1fef7d1b8
wait for a moment
and on cassandra server terminal you will see:
INFO 10:50:36 Removing host: 199553f1-f310-41e1-b4a4-f5a1fef7d1b8
INFO 10:50:36 Sleeping for 30000ms to ensure /192.168.1.201 does not change
INFO 10:51:06 Advertising removal for /192.168.1.201
INFO 10:51:07 [Stream #60607920-429e-11e6-b2ec-cbf9a478e7df] Executing streaming plan for Restore replica count
INFO 10:51:07 Handshaking version with /192.168.1.110
...
INFO 10:51:07 Completing removal of /192.168.1.201
and now , execute nodetool status, you will see
finish.