It is worth checking the replication factor before modifying:

./path/to/kafka/bin/kafka-topics.sh --describe --zookeeper localhost:2181 --topic test-topic

Topic:test-topic        PartitionCount:2        ReplicationFactor:1     Configs:
        Topic: demo-topic       Partition: 0    Leader: 0       Replicas: 0     Isr: 0
        Topic: demo-topic       Partition: 1    Leader: 1       Replicas: 1     Isr: 1

It can be seen here that the replication factor is 1.

To update to a replication factor of e.g. 3 firstly create a json file with a new reassignment plan. Call it e.g. reassignment-plan.json:

List all registered VM ID’s:

vim-cmd vmsvc/getallvms

Power off vm:

vim-cmd vmsvc/power.off VMID

Check vm power status:

vim-cmd vmsvc/power.getstate VMID

vim-cmd vmsvc/getallvms

Create the following conf file:

vim /etc/nginx/conf.d/blockips.conf

Enter the following e.g. :

deny 1.2.3.4;
deny 95.32.45.0/24;

Restart nginx

sudo launchctl stop com.openssh.sshd
sudo launchctl start com.openssh.sshd