Hadoop集群配置免密登录方法

墨蓝 2023-07-04 15:36 4阅读 0赞

Hadoop集群包含1个主节点和3个从节点，需要实现各节点之间的免密码登录，下面介绍具体的实现方法。

### 一、Hadoop集群环境 ###

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### 二、免密登录原理 ###

每台主机authorized\_keys文件里面包含的主机（ssh密钥），该主机都能无密码登录，所以只要每台主机的authorized\_keys文件里面都放入其他主机（需要无密码登录的主机）的ssh密钥就行了。

###  三、实现方法 ###

**1. 配置每个节点的hosts文件**

\#vim /etc/hosts  
1 192.168.44.3 hadoop01  
2 192.168.44.4 hadoop02  
3 192.168.44.5 hadoop03  
4 192.168.44.6 hadoop04

**2. 每个节点生成ssh密钥**

\[root@hadoop01 ~\]\# ssh-keygen -t rsa  
Generating public/private rsa key pair.  
Enter file in which to save the key (/root/.ssh/id\_rsa):  
Created directory '/root/.ssh'.  
Enter passphrase (empty for no passphrase):  
Enter same passphrase again:  
Your identification has been saved in /root/.ssh/id\_rsa.  
Your public key has been saved in /root/.ssh/id\_rsa.pub.  
.....................

\[root@hadoop01 .ssh\]\# ls  
id\_rsa  id\_rsa.pub

执行命令后会在~目录下生成.ssh文件夹，里面包含id\_rsa和id\_rsa.pub两个文件。

注：使用ssh-keygen -t rsa -P '' -f ~/.ssh/id\_rsa命令可避免上述交互式操作。

**3. 在主节点上将公钥拷到一个特定文件authorized\_keys中。**

\[root@hadoop01 ~\]\# cd .ssh  
\[root@hadoop01 .ssh\]\# ls  
id\_rsa  id\_rsa.pub  
\[root@hadoop01 .ssh\]\# cp id\_rsa.pub authorized\_keys  
\[root@hadoop01 .ssh\]\# ls  
authorized\_keys  id\_rsa  id\_rsa.pub

**4. 将authorized\_keys文件拷到下一个节点，并将该节点的ssh密钥id\_rsa.pub加入该文件中。**

\#在hadoop01上使用scp命令实现远程文件拷贝  
\[root@hadoop01 .ssh\]\# scp authorized\_keys  root@hadoop02:/root/.ssh/  
The authenticity of host 'hadoop02 (192.168.44.11)' can't be established.  
ECDSA key fingerprint is SHA256:MyB1zs0E3J/fm8pC0AN8ycsgEIBNHtUqd9xS0WAyv3s.  
ECDSA key fingerprint is MD5:88:48:3a:ba:3e:14:a7:d7:86:f6:51:74:00:10:f9:00.  
Are you sure you want to continue connecting (yes/no)? yes  
Warning: Permanently added 'hadoop02,192.168.44.11' (ECDSA) to the list of known hosts.  
root@hadoop02's password:  
authorized\_keys                                                                100%  395  306.2KB/s  00:00

\#登录hadoop02主机

\[root@hadoop02 ~\]\# cd .ssh/  
\[root@hadoop02 .ssh\]\# ls  
authorized\_keys id\_rsa id\_rsa.pub  
\[root@hadoop02 .ssh\]\# cat id\_rsa.pub >> authorized\_keys \#使用cat追加方式

**5. 重复第4步的操作，依次将hadoop03、hadoop04节点的ssh密钥加入到authorized\_keys文件中，并将hadoop04节点生成的authorized\_keys文件拷贝到其他三个节点（hadoop01、hadoop02、hadoop03）即可。**

\#登录hadoop03主机，将ssh密钥加入authorized\_keys文件中  
\[root@hadoop03 .ssh\]\# cat id\_rsa.pub >> authorized\_keys  
\[root@hadoop03 .ssh\]\# scp authorized\_keys root@hadoop04:/root/.ssh/

\#登录hadoop04主机，将ssh密钥加入authorized\_keys文件中  
\[root@hadoop04 .ssh\]\# cat id\_rsa.pub >> authorized\_keys

\#将最后生成的authorized\_keys文件分别拷贝到hadoop01、hadoop02和hadoop03  
\[root@hadoop04 .ssh\]\# scp authorized\_keys root@hadoop01:/root/.ssh/  
\[root@hadoop04 .ssh\]\# scp authorized\_keys root@hadoop02:/root/.ssh/  
\[root@hadoop04 .ssh\]\# scp authorized\_keys root@hadoop03:/root/.ssh/

**6. 验证免密登录**

使用ssh 用户名@节点名或ssh ip地址命令验证免密码登录。

\[root@hadoop01 .ssh\]\# ssh root@hadoop02  
Last login: Tue Feb 12 03:59:46 2019 from 192.168.44.1

\[root@hadoop02 .ssh\]\# ssh root@hadoop01  
Last login: Tue Feb 12 21:27:24 2019 from hadoop04

\[root@hadoop03 .ssh\]\# ssh root@hadoop04  
Last login: Tue Feb 12 04:00:47 2019 from 192.168.44.1

\[root@hadoop04 .ssh\]\# ssh root@hadoop01  
Last login: Tue Feb 12 21:26:44 2019 from hadoop02

[format_png]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly93d3cubGludXhpZGMuY29tL3VwbG9hZC8yMDE5XzAyLzE5MDIxMzE3MzU2ODMxMS5wbmc?x-oss-process=image/format,png