hive启动后，出现以下异常
hive> show databases; FAILED: Error in metadata: MetaException(message:Got exception: java.net.ConnectException Call to centos7-01/192.168.146.135:9000 failed on connection exception: java.net.ConnectException: Connection refused) FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask
原因是hadoop集群没有启动（注意端口号9000）
[root@centos7-01 conf]# start-all.sh //启动hadoop starting namenode, logging to /opt/sw/hadoop-0.20.2/bin/../logs/hadoop-root-namenode-centos7-01.out centos7-03: starting datanode, logging to /opt/sw/hadoop-0.20.2/bin/../logs/hadoop-root-datanode-centos7-03.out centos7-02: starting datanode, logging to /opt/sw/hadoop-0.20.2/bin/../logs/hadoop-root-datanode-centos7-02.out centos7-01: starting secondarynamenode, logging to /opt/sw/hadoop-0.20.2/bin/../logs/hadoop-root-secondarynamenode-centos7-01.out starting jobtracker, logging to /opt/sw/hadoop-0.20.2/bin/../logs/hadoop-root-jobtracker-centos7-01.out centos7-03: starting tasktracker, logging to /opt/sw/hadoop-0.20.2/bin/../logs/hadoop-root-tasktracker-centos7-03.out centos7-02: starting tasktracker, logging to /opt/sw/hadoop-0.20.2/bin/../logs/hadoop-root-tasktracker-centos7-02.out [root@centos7-01 conf]# jps 2608 NameNode 2753 SecondaryNameNode 2818 JobTracker 2904 Jps 2475 RunJar
就没问题了
hive> show databases; OK default Time taken: 1.104 seconds
FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask
原文：https://www.cnblogs.com/wwzyy/p/9233238.html