HBase笔记之踩坑记录：Java远程连接到HBase
HBase服务器在一台腾讯云上，本地Windows系统连不上，代码如下：
package cc11001100.hbase.baseOperation;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import java.io.IOException;
/**
* @author CC11001100
*/
public class JavaConnectToHbaseTest {
public static void main(String[] args) throws IOException {
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "xx.xx.xx.xx");
conf.set("hbase.zookeeper.property.clientPort", "2181");
Connection conn = ConnectionFactory.createConnection(conf);
System.out.println(conn);
Admin admin = conn.getAdmin();
System.out.println(admin.tableExists(TableName.valueOf("test:user")));
}
}
输出如下：
hconnection-0x674658f7
Exception in thread "main" org.apache.hadoop.hbase.client.RetriesExhaustedException: Failed after attempts=16, exceptions:
Sun Dec 09 23:41:54 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:41:54 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: Call to localhost/127.0.0.1:16000 failed on local exception: org.apache.hadoop.hbase.ipc.FailedServerException: This server is in the failed servers list: localhost/127.0.0.1:16000
Sun Dec 09 23:41:54 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: Call to localhost/127.0.0.1:16000 failed on local exception: org.apache.hadoop.hbase.ipc.FailedServerException: This server is in the failed servers list: localhost/127.0.0.1:16000
Sun Dec 09 23:41:54 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: Call to localhost/127.0.0.1:16000 failed on local exception: org.apache.hadoop.hbase.ipc.FailedServerException: This server is in the failed servers list: localhost/127.0.0.1:16000
Sun Dec 09 23:41:55 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: Call to localhost/127.0.0.1:16000 failed on local exception: org.apache.hadoop.hbase.ipc.FailedServerException: This server is in the failed servers list: localhost/127.0.0.1:16000
Sun Dec 09 23:41:57 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:42:00 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:42:06 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:42:17 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:42:28 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:42:39 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:42:50 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.net.ConnectException: Call to localhost/127.0.0.1:16000 failed on connection exception: org.apache.hbase.thirdparty.io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: localhost/127.0.0.1:16000
Sun Dec 09 23:43:10 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /hbase/master
Sun Dec 09 23:43:31 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /hbase/master
Sun Dec 09 23:43:51 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /hbase/master
Sun Dec 09 23:44:11 CST 2018, RpcRetryingCaller{globalStartTime=1544370111222, pause=100, maxAttempts=16}, org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /hbase/master
at org.apache.hadoop.hbase.client.RpcRetryingCallerImpl.callWithRetries(RpcRetryingCallerImpl.java:144)
at org.apache.hadoop.hbase.client.HBaseAdmin.executeCallable(HBaseAdmin.java:3084)
at org.apache.hadoop.hbase.client.HBaseAdmin.executeCallable(HBaseAdmin.java:3076)
at org.apache.hadoop.hbase.client.HBaseAdmin.listTableDescriptors(HBaseAdmin.java:323)
at org.apache.hadoop.hbase.client.HBaseAdmin.listTableDescriptors(HBaseAdmin.java:312)
at cc11001100.hbase.tableOperation.TableOperationUsageDemo.main(TableOperationUsageDemo.java:43)
Caused by: org.apache.hadoop.hbase.MasterNotRunningException: java.io.IOException: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /hbase/master
at org.apache.hadoop.hbase.client.ConnectionImplementation$MasterServiceStubMaker.makeStub(ConnectionImplementation.java:1157)
at org.apache.hadoop.hbase.client.ConnectionImplementation.getKeepAliveMasterService(ConnectionImplementation.java:1216)
at org.apache.hadoop.hbase.client.ConnectionImplementation.getMaster(ConnectionImplementation.java:1205)
at org.apache.hadoop.hbase.client.MasterCallable.prepare(MasterCallable.java:57)
at org.apache.hadoop.hbase.client.RpcRetryingCallerImpl.callWithRetries(RpcRetryingCallerImpl.java:105)
... 5 more
Caused by: java.io.IOException: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /hbase/master
at org.apache.hadoop.hbase.client.ConnectionImplementation.get(ConnectionImplementation.java:1994)
at org.apache.hadoop.hbase.client.ConnectionImplementation.access$500(ConnectionImplementation.java:138)
at org.apache.hadoop.hbase.client.ConnectionImplementation$MasterServiceStubMaker.makeStubNoRetries(ConnectionImplementation.java:1118)
at org.apache.hadoop.hbase.client.ConnectionImplementation$MasterServiceStubMaker.makeStub(ConnectionImplementation.java:1151)
... 9 more
Caused by: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /hbase/master
at org.apache.zookeeper.KeeperException.create(KeeperException.java:111)
at org.apache.zookeeper.KeeperException.create(KeeperException.java:51)
at org.apache.hadoop.hbase.zookeeper.ReadOnlyZKClient$ZKTask$1.exec(ReadOnlyZKClient.java:174)
at org.apache.hadoop.hbase.zookeeper.ReadOnlyZKClient.run(ReadOnlyZKClient.java:329)
at java.lang.Thread.run(Thread.java:748)
可以看到第一行打印出了conn，说明成功连接到了zookeeper服务器，否则这一步就会报错了，所以是在从zookeeper取得master信息尝试去连接master的时候出错的。
然后看了下报错信息中的地址我就很奇怪，为什么是连接的localhost:16000呢，这个信息存放到zookeeper上，登录到zookeeper看下当前的master绑定到哪里了：
悲剧了，为什么是localhost呢难道只监听了回环地址吗，然后在master机器上看16000端口的监听情况：
我本来以为在hbase-site.xml中会有一个选项用来设置master监听的网卡地址，毕竟这是业内约定俗成的做法了，鬼知道hbase这么奇葩，折腾半天也没找到相关的设置，倒是找到了另一种方法解决这个问题。
hbase会绑定到当前的hostname所解析到的地址，所以手动改下hostname，然后在/etc/hosts中将hostname解析到要绑定的网卡上，启动时就会去解析hostname，然后监听到解析到的ip上。
修改hostname可以修改/etc/hostname，这个永久有效但是需要重启生效，或者使用hostname临时修改hostname：
[root@foobar ~]# hostname master
然后在/etc/hosts中加入一条，将主机名解析到要绑定的ip上：
10.xx.xx.xx master
启动hbase，查看端口监听情况：
然后再去zookeeper看下master绑定情况：
当客户端来zookeeper寻找master的时候会根据得到的master的域名解析到的ip去寻找，所以还需要在客户端加一条master到服务器公网ip的映射，我这里是Windows系统，在C:\Windows\System32\drivers\etc\hosts中加一个映射：
140.xx.xx.xx master
Java代码无需修改，再运行一次：
hconnection-0x5a56cdac true
OK，成功连接。
总结：
我想了一下这样设计的原因应该就是master的地址是存在zookeeper上的，其它客户端去zookeeper取这个地址然后连接，这是一个常量，如果放ip的话，会涉及到网卡的内网ip和外网ip的处理，因为hbase要监听在网卡的内网地址上，如果可以配置的话在配置文件中的必须是一个内网ip，如果将这个内网ip给zookeeper，内网的其它机器能够连接上，但外网连接就悲剧了，所以比较灵活的方式还是放域名（这里是hostname），这样客户端根据自己的位置将hostname解析为不同的地址，内网的话解析为内网地址，外网的话解析为公网地址，整体上没啥毛病，只是不太好的部分是监听的时候从hostname到网卡ip的这一段的处理有点不太好，个人感觉不如提供多提供两个选项，一个用来配置监听网卡ip，默认是0.0.0.0，另一个是配置一个域名作为放到zookeeper上的master的地址，默认取当前的hostname。
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