目的
添加Hadoop-Slave2到集群。
| 主机 | IP |
|---|---|
| Hadoop-Master | 192.168.241.140 |
| Hadoop-Slave | 192.168.241.141 |
| Hadoop-Slave2 | 192.168.241.142 |
修改Hadoop-Master配置文件
修改slaves文件
/home/fwj/hadoop-2.9.1/etc/hadoop/slaves增加新节点：
hadoop-slave
hadoop-slave2
修改hosts文件
/etc/hosts增加ip与hostname的映射：
192.168.241.140 Hadoop-Master
192.168.241.141 Hadoop-Slave
192.168.241.142 Hadoop-Slave2
拷贝配置文件到Hadoop-Slave
拷贝slaves文件：
scp /home/fwj/hadoop-2.9.1/etc/hadoop/slaves fwj@Hadoop-Slave:~/hadoop-2.9.1/etc/hadoop/slaves
Hadoop-Slave的/etc/hosts增加ip与hostname的映射：
192.168.241.140 Hadoop-Master
192.168.241.141 Hadoop-Slave
192.168.241.142 Hadoop-Slave2
克隆Hadoop-Master到Hadoop-Slave2
克隆成功后启动Hadoop-Slave2，配置IP地址和hostname。
/etc/network/interfaces文件：
auto eth0
iface eth0 inet static
address 192.168.241.142
netmask 255.255.255.0
gateway 192.168.241.2
/etc/hostname文件：
Hadoop-Slave2
重启服务器。
配置免密登录
1、在Hadoop-Master节点上执行ssh-keygen -t rsa -P ''
2、把id_rsa.pub追加到授权的key里面cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
3、修改/etc/ssh/sshd_config，检查下面内容前面的#是否有去掉
RSAAuthentication yes # 启用 RSA 认证
PubkeyAuthentication yes # 启用公钥私钥配对认证方式
AuthorizedKeysFile %h/.ssh/authorized_keys # 公钥文件路径
4、重启ssh服务，service ssh restart
5、复制公钥到所有的Slave
ssh-copy-id fwj@hadoop-slave
ssh-copy-id fwj@hadoop-slave2
Hadoop-Master启动Hadoop
start-all.sh
验证是否成功
fwj@Hadoop-Master:~$ hdfs dfsadmin -report
输出：
Configured Capacity: 19810402304 (18.45 GB)
Present Capacity: 12403527680 (11.55 GB)
DFS Remaining: 12402741248 (11.55 GB)
DFS Used: 786432 (768 KB)
DFS Used%: 0.01%
Under replicated blocks: 0
Blocks with corrupt replicas: 0
Missing blocks: 0
Missing blocks (with replication factor 1): 0
Pending deletion blocks: 0
-------------------------------------------------
Live datanodes (2):
Name: 192.168.241.141:50010 (Hadoop-Slave)
Hostname: Hadoop-Slave
Decommission Status : Normal
Configured Capacity: 9905201152 (9.22 GB)
DFS Used: 757760 (740 KB)
Non DFS Used: 2625122304 (2.44 GB)
DFS Remaining: 6752571392 (6.29 GB)
DFS Used%: 0.01%
DFS Remaining%: 68.17%
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: Tue Sep 18 15:29:36 CST 2018
Last Block Report: Tue Sep 18 15:02:39 CST 2018
Name: 192.168.241.142:50010 (Hadoop-Slave2)
Hostname: Hadoop-Slave2
Decommission Status : Normal
Configured Capacity: 9905201152 (9.22 GB)
DFS Used: 28672 (28 KB)
Non DFS Used: 3728252928 (3.47 GB)
DFS Remaining: 5650169856 (5.26 GB)
DFS Used%: 0.00%
DFS Remaining%: 57.04%
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: Tue Sep 18 15:29:35 CST 2018
Last Block Report: Tue Sep 18 15:10:38 CST 2018