1、 HBase is able to connect to ZooKeeper but the connection closes immediately
hbase(main):001:0> list
TABLE
ERROR: org.apache.hadoop.hbase.ZooKeeperConnectionException: HBase is able to connect to ZooKeeper but the connection closes immediately. This could be a sign that the server has too many connections (30 is the default). Consider inspecting your ZK server logs
for that error and then make sure you are reusing HBaseConfiguration as often as you can. See HTable's javadoc for more information.
Here is some help for this command:
List all tables in hbase. Optional regular expression parameter could
be used to filter the output. Examples:
hbase> list
hbase> list 'abc.*'
hbase(main):002:0> exit
解决方法：
修改/etc/hosts:
#127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
#::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
将原有的前2行去掉。