<sub>Posted on January 13, 2016 by [https://il.linkedin.com/in/knesenko '''Kiril Nesenko''']</sub><br />
 <br />
 In my previous How-To [[Install and Configure a Production Ready Mesos Cluster on PhotonOS]]. In this How-To I am going to explain how to install and configure Marathon for Mesos cluster. All the following steps should be done on each Mesos master.
 First, download Marathon:
 <source lang="bash" enclose="div">
 root@pt-mesos-master2 [ ~ ]# mkdir -p  /opt/mesosphere/marathon/ && cd /opt/mesosphere/marathon/
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]#  curl -O http://downloads.mesosphere.com/marathon/v0.13.0/marathon-0.13.0.tgz
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# tar -xf marathon-0.13.0.tgz
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# mv marathon-0.13.0 marathon
 </source><br />
 Create a configuration for Marathon:
 <source lang="bash" enclose="div">
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# ls -l /etc/marathon/conf/
 total 8
 -rw-r--r-- 1 root root 68 Dec 24 14:33 master
 -rw-r--r-- 1 root root 71 Dec 24 14:33 zk
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# cat /etc/marathon/conf/*
 zk://192.168.0.2:2181,192.168.0.1:2181,192.168.0.3:2181/mesos
 zk://192.168.0.2:2181,192.168.0.1:2181,192.168.0.3:2181/marathon
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# cat /etc/systemd/system/marathon.service
 [Unit]
 Description=Marathon
 After=network.target
 Wants=network.target
  
 [Service]
 Environment="JAVA_HOME=/opt/OpenJDK-1.8.0.51-bin"
 ExecStart=/opt/mesosphere/marathon/bin/start \
     --master zk://192.168.0.2:2181,192.168.0.1:2181,192.168.0.3:2181/mesos \
     --zk zk://192.168.0.2:2181,192.168.0.1:2181,192.168.0.3:2181/marathon
 Restart=always
 RestartSec=20
  
 [Install]
 WantedBy=multi-user.target
 </source><br />
 Finally, we need to change the Marathon startup script, since PhotonOS do not use the standard JRE. Make sure you add JAVA_HOME to Java path:
 <source lang="bash" enclose="div">
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# tail -n3 /opt/mesosphere/marathon/bin/start
 # Start Marathon
 marathon_jar=$(find "$FRAMEWORK_HOME"/target -name 'marathon-assembly-*.jar' | sort | tail -1)
 exec "${JAVA_HOME}/bin/java" "${java_args[@]}" -jar "$marathon_jar" "${app_args[@]}"
 </source><br />
 Now we can start the Marthon service:
 <source lang="bash" enclose="div">
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# systemctl start marathon
 root@pt-mesos-master2 [ /opt/mesosphere/marathon ]# ps -ef | grep marathon
 root     15821     1 99 17:14 ?        00:00:08 /opt/OpenJDK-1.8.0.51-bin/bin/java -jar /opt/mesosphere/marathon/bin/../target/scala-2.11/marathon-assembly-0.13.0.jar --master zk://192.168.0.2:2181,192.168.0.1:2181,192.168.0.3:2181/mesos --zk zk://192.168.0.2:2181,192.168.0.1:2181,192.168.0.3:2181/marathon
 root     15854 14692  0 17:14 pts/0    00:00:00 grep --color=auto marathon
 </source><br />
 <br /><br />
 Next - [[Install and Configure DCOS CLI for Mesos]]