我尝试在Ubuntu系统下为zeppelin.conf的命令设置sudo service zeppelin start：
description "zeppelin"
start on (local-filesystems and net-device-up IFACE!=lo)
stop on shutdown
# Respawn the process on unexpected termination
respawn
# respawn the job up to 7 times within a 5 second period.
# If the job exceeds these values, it will be stopped and marked as failed.
respawn limit 7 5
# zeppelin was installed in /home/x/zeppelin in this example
chdir /home/x/zeppelin
exec bin/zeppelin-daemon.sh upstart
但是当我执行命令sudo service zeppelin start时，出现错误，我不知道如何解决：
Failed to start zeppelin.service: Unit zeppelin.service not found.
这是错误日志：
ZEPPELIN_CLASSPATH: ::/home/x/zeppelin/lib/interpreter/*:/home/x/zeppelin/lib/*:/home/x/zeppelin/*::/home/x/zeppelin/conf
nice: "/usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java/bin/java": Not a directory
我设置的JAVA_HOME是正确的：
JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64/jre"