Setting up Kafka on Ubuntu-18.04. Credits: https://www.digitalocean.com/community/tutorials/how-to-install-apache-kafka-on-ubuntu-18-04

kafka.service

[Unit]
Description=Kafka
Requires=zookeeper.service
After=zookeeper.service

[Service]
Type=simple
ExecStart=/bin/sh -c '/home/ubuntu/.kafka/bin/kafka-server-start.sh /home/ubuntu/.kafka/config/server.properties > /home/ubuntu/.kafka/kafka.log 2>&1'
ExecStop=/home/ubuntu/.kafka/bin/kafka-server-stop.sh
Restart=on-abnormal

[Install]
WantedBy=multi-user.target

zookeeper.service

[Unit]
Description=Zookeeper
After=syslog.target
After=network.target
After=systemd-vconsole-setup.service

[Service]
Type=simple
ExecStart=/home/ubuntu/.kafka/bin/zookeeper-server-start.sh /home/ubuntu/.kafka/config/zookeeper.properties
ExecStop=/home/ubuntu/.kafka/bin/zookeeper-server-stop.sh
Restart=on-abnormal

[Install]
WantedBy=multi-user.target