Display ZooKeeper startup options.
Use print-cmd action on zkServer.sh control script to display startup parameters.
$ sudo -u zookeeper /opt/zookeeper/zookeeper/bin/zkServer.sh print-cmd
/usr/bin/java ZooKeeper JMX enabled by default Using config: /opt/zookeeper/zookeeper/bin/../conf/zoo.cfg "java" -Dzookeeper.log.dir="/opt/zookeeper/zookeeper/bin/../logs" -Dzookeeper.log.file="zookeeper-zookeeper-server-zookeeper2.log" -Dzookeeper.root.logger="INFO,CONSOLE" -XX:+HeapDumpOnOutOfMemoryError -XX:OnOutOfMemoryError='kill -9 %p' -cp "/opt/zookeeper/zookeeper/bin/../zookeeper-server/target/classes:/opt/zookeeper/zookeeper/bin/../build/classes:/opt/zookeeper/zookeeper/bin/../zookeeper-server/target/lib/*.jar:/opt/zookeeper/zookeeper/bin/../build/lib/*.jar:/opt/zookeeper/zookeeper/bin/../lib/zookeeper-prometheus-metrics-3.7.0.jar:/opt/zookeeper/zookeeper/bin/../lib/zookeeper-jute-3.7.0.jar:/opt/zookeeper/zookeeper/bin/../lib/zookeeper-3.7.0.jar:/opt/zookeeper/zookeeper/bin/../lib/snappy-java-1.1.7.7.jar:/opt/zookeeper/zookeeper/bin/../lib/slf4j-log4j12-1.7.30.jar:/opt/zookeeper/zookeeper/bin/../lib/slf4j-api-1.7.30.jar:/opt/zookeeper/zookeeper/bin/../lib/simpleclient_servlet-0.9.0.jar:/opt/zookeeper/zookeeper/bin/../lib/simpleclient_hotspot-0.9.0.jar:/opt/zookeeper/zookeeper/bin/../lib/simpleclient_common-0.9.0.jar:/opt/zookeeper/zookeeper/bin/../lib/simpleclient-0.9.0.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-transport-native-unix-common-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-transport-native-epoll-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-transport-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-resolver-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-handler-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-common-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-codec-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/netty-buffer-4.1.59.Final.jar:/opt/zookeeper/zookeeper/bin/../lib/metrics-core-4.1.12.1.jar:/opt/zookeeper/zookeeper/bin/../lib/log4j-1.2.17.jar:/opt/zookeeper/zookeeper/bin/../lib/jline-2.14.6.jar:/opt/zookeeper/zookeeper/bin/../lib/jetty-util-ajax-9.4.38.v20210224.jar:/opt/zookeeper/zookeeper/bin/../lib/jetty-util-9.4.38.v20210224.jar:/opt/zookeeper/zookeeper/bin/../lib/jetty-servlet-9.4.38.v20210224.jar:/opt/zookeeper/zookeeper/bin/../lib/jetty-server-9.4.38.v20210224.jar:/opt/zookeeper/zookeeper/bin/../lib/jetty-security-9.4.38.v20210224.jar:/opt/zookeeper/zookeeper/bin/../lib/jetty-io-9.4.38.v20210224.jar:/opt/zookeeper/zookeeper/bin/../lib/jetty-http-9.4.38.v20210224.jar:/opt/zookeeper/zookeeper/bin/../lib/javax.servlet-api-3.1.0.jar:/opt/zookeeper/zookeeper/bin/../lib/jackson-databind-2.10.5.1.jar:/opt/zookeeper/zookeeper/bin/../lib/jackson-core-2.10.5.jar:/opt/zookeeper/zookeeper/bin/../lib/jackson-annotations-2.10.5.jar:/opt/zookeeper/zookeeper/bin/../lib/commons-cli-1.4.jar:/opt/zookeeper/zookeeper/bin/../lib/audience-annotations-0.12.0.jar:/opt/zookeeper/zookeeper/bin/../zookeeper-*.jar:/opt/zookeeper/zookeeper/bin/../zookeeper-server/src/main/resources/lib/*.jar:/opt/zookeeper/zookeeper/bin/../conf:" -Xmx1000m -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.local.only=false org.apache.zookeeper.server.quorum.QuorumPeerMain "/opt/zookeeper/zookeeper/bin/../conf/zoo.cfg" > "/opt/zookeeper/zookeeper/bin/../logs/zookeeper-zookeeper-server-zookeeper2.out" 2>&1 < /dev/null