centOS7.0 下配置Hadoop集群,Slave1报错：failed on socket timeout exception: java.net.NoRouteToHostException


Hadoop版本：2.5.0

在配置Hadoop集群时，在Master上 启动目录/usr/hadoop/sbin/下的./start-all.sh后，在Master主机上

[hadoop@Master sbin]$ ./start-all.sh

This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh

Starting namenodes on [Master.Hadoop]

Master.Hadoop: starting namenode, logging to /usr/hadoop/logs/hadoop-hadoop-namenode-Master.Hadoop.out

192.168.86.129: starting datanode, logging to /usr/hadoop/logs/hadoop-hadoop-datanode-Slaver1.Hadoop.out

Starting secondary namenodes [0.0.0.0]

0.0.0.0: starting secondarynamenode, logging to /usr/hadoop/logs/hadoop-hadoop-secondarynamenode-Master.Hadoop.out

starting yarn daemons

starting resourcemanager, logging to /usr/hadoop/logs/yarn-hadoop-resourcemanager-Master.Hadoop.out

192.168.86.129: starting nodemanager, logging to /usr/hadoop/logs/yarn-hadoop-nodemanager-Slaver1.Hadoop.out

[hadoop@Master sbin]$ jps

10474 Jps

10217 ResourceManager

9885 NameNode

10069 SecondaryNameNode

可见已经成功启动，在Slave1 datanode节点机上

[hadoop@Slave1 ~]$ jps

5098 NodeManager

5000 DataNode

5184 Jps

可见也已经成功启动，但是当dfsadmin -report时，报出下面错误

[hadoop@Slave1 ~]$ hadoop dfsadmin -report

DEPRECATED: Use of this script to execute hdfs command is deprecated.

Instead use the hdfs command for it.

14/09/29 10:10:58 INFO ipc.Client: Retrying connect to server: Master.Hadoop/192.168.86.128:9000. Already tried 0 time(s); maxRetries=45

report: No Route to Host from Slave1.Hadoop/192.168.86.129 to Master.Hadoop:9000 failed on socket timeout exception: java.net.NoRouteToHostException: No route to host; For more details see:
http://wiki.apache.org/hadoop/NoRouteToHost

经过查找，发现是因为防火墙没有关闭！

在以往Linux版本上，使用service iptables stop命令进行关闭防火墙，但是当道centOS7.0后，改命令就无法使用。

centOS7.0上面的服务都通过systemctl命令进行start、stop、restart。

而且在centOS7.0上，防火墙也不再是iptables,而是firewall,所以在Master和Slave1上均执行(先切换到root用户)

[hadoop@Slave1 ~]$ su - root

Password:

Last login: Mon Sep 29 10:20:31 CST 2014 on pts/0

[root@Slave1 ~]# systemctl stop firewalld.service

现在再看一下Master和Slave1的Hadoop的存储情况

MASTER

[hadoop@Master sbin]$ hadoop dfadmin -report

Error: Could not find or load main class dfadmin

[hadoop@Master sbin]$ hadoop dfsadmin -report

DEPRECATED: Use of this script to execute hdfs command is deprecated.

Instead use the hdfs command for it.

Configured Capacity: 12572426240 (11.71 GB)

Present Capacity: 6669115392 (6.21 GB)

DFS Remaining: 6669111296 (6.21 GB)

DFS Used: 4096 (4 KB)

DFS Used%: 0.00%

Under replicated blocks: 0

Blocks with corrupt replicas: 0

Missing blocks: 0

-------------------------------------------------

Live datanodes (1):

Name: 192.168.86.129:50010 (Slaver1.Hadoop)

Hostname: Slaver1.Hadoop

Decommission Status : Normal

Configured Capacity: 12572426240 (11.71 GB)

DFS Used: 4096 (4 KB)

Non DFS Used: 5903310848 (5.50 GB)

DFS Remaining: 6669111296 (6.21 GB)

DFS Used%: 0.00%

DFS Remaining%: 53.05%

Configured Cache Capacity: 0 (0 B)

Cache Used: 0 (0 B)

Cache Remaining: 0 (0 B)

Cache Used%: 100.00%

Cache Remaining%: 0.00%

Xceivers: 1

Last contact: Mon Sep 29 10:57:04 CST 2014

SLAVE1

[hadoop@Slaver1 ~]$ hadoop dfsadmin -report

DEPRECATED: Use of this script to execute hdfs command is deprecated.

Instead use the hdfs command for it.

Configured Capacity: 12572426240 (11.71 GB)

Present Capacity: 6669012992 (6.21 GB)

DFS Remaining: 6669008896 (6.21 GB)

DFS Used: 4096 (4 KB)

DFS Used%: 0.00%

Under replicated blocks: 0

Blocks with corrupt replicas: 0

Missing blocks: 0

-------------------------------------------------

Live datanodes (1):

Name: 192.168.86.129:50010 (Slaver1.Hadoop)

Hostname: Slaver1.Hadoop

Decommission Status : Normal

Configured Capacity: 12572426240 (11.71 GB)

DFS Used: 4096 (4 KB)

Non DFS Used: 5903413248 (5.50 GB)

DFS Remaining: 6669008896 (6.21 GB)

DFS Used%: 0.00%

DFS Remaining%: 53.04%

Configured Cache Capacity: 0 (0 B)

Cache Used: 0 (0 B)

Cache Remaining: 0 (0 B)

Cache Used%: 100.00%

Cache Remaining%: 0.00%

Xceivers: 1

Last contact: Mon Sep 29 10:28:18 CST 2014