Here is the log:
Dec 17 18:53:01 masternodes-12345 elasticsearch[17567]: PWD=/usr/local/elasticsearch
Dec 17 18:53:01 masternodes-12345 elasticsearch[17567]: LANG=en_US.UTF-8
Dec 17 18:53:01 masternodes-12345 elasticsearch[17567]: ES_JVM_OPTIONS=/usr/local/etc/elasticsearch/jvm.options
Dec 17 18:53:01 masternodes-12345 elasticsearch[17567]: SHLVL=1
Dec 17 18:53:01 masternodes-12345 elasticsearch[17567]: ES_PATH_CONF=/usr/local/etc/elasticsearch
Dec 17 18:53:01 masternodes-12345 elasticsearch[17567]: _=/bin/env
Dec 17 18:53:01 masternodes-12345 elasticsearch[17567]: OLDPWD=/
Dec 17 18:53:01 masternodes-12345 runuser[17578]: pam_unix(runuser:session): session opened for user elasticsearch by (uid=0)
Dec 17 18:53:08 masternodes-12345 elasticsearch[17567]: Exception in thread "main" org.elasticsearch.bootstrap.BootstrapException: org.elasticsearch.cli.UserException: unable to create temporary keystore at [/u
Dec 17 18:53:08 masternodes-12345 elasticsearch[17567]: Likely root cause: java.nio.file.AccessDeniedException: /usr/local/etc/elasticsearch/elasticsearch.keystore.tmp