集群间相互ssh免密访问

SSH配置

的集群中的每台主机上打开配置

sudo vim /etc/ssh/sshd_config

开启下面的选项

RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile .ssh/authorized_keys

生成SSH密钥

的集群中的每台主机上执行下面命令，一路回车，可生成本机的rsa类型的密钥。

ssh-keygen -t rsa

执行完之后在~/.ssh/目录下会生成一个保存有公钥的文件：id_rsa.pub

把公钥写入authorized_keys文件

把自己的公钥拷贝到集群中的Master机

ssh-copy-id hadoop@HadoopMaster

最终在Master机上生成如下的内容的~/.ssh/authorized_keys文件：

ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEArYU2kMXsu75Gzwvuby7OoGzC7GVwxVo+ol/7nJVD    BpKpJLRHRe/d2HSNe9ZZRWLK2tU0e41baMxrYRoAKJA2ujcWfy7t57c3ArO9hA7KJy7MqMiT8WHQ    M3I2Afsx6sVKeQU/czDLXHn+KjwKbR8z0tuycgtxgkaWx1PCpCKeFDAXDVvxYcurSUNaIGL5Egzu    Iy97N52ld/WxUZnRRsTPdpW88JkhWdOV1Bdo4O67rNv5tSYKHXfPwqi8NekqoHIExgVRsHLvM8fe    xvV4mo8lXYdQPRCyrtM9/V+4kSW8eaBO7w6hM9YVZIspSqx0+OqibWTvqSmiAVh0JmUT0MCeVQ==     hadoop@HadoopMaster
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA7n27x4qSzRQNGQAL+rT1+91IQnM9cwZYFeSUzrJD    GDfwCTJMKnRBYxrDMxTAM6MKjfwwkPzXnbKHLQnDiJKUSdF8H2xcgDMBJLssVQjOc2jSEg/VppQN    hJwObbIL3k1FbU2KxkOp7yW5PIodZrgUwlH5wdXtfsPKimvv72uA1KUiqPbYA3ZJqXw9Bt87K6Sv    IAkvUjshnfaS+wNEBVwW1dhXyz6DHuY+Tn9330+1oYfdmgSjS4ZqvZVothhhV58DNwzAYwINCpBA    tkjFbk/SOf0q/4rSJRpe2yH9xOuZdwqXMfk3dkp0UFZkV2EVSLyaCNKwTbSuKN75FWhgl8QB7w==     hadoop@HadoopSlave1
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAw91O/1NWnbr6/vop+xwnqR/XYNpwkWselzyHNqgD    PYgXXsDHsvOZbpTX7pgOTgVSmlZetCdX4C1lsc/PO8IitvvBS/qWU216lXaqlW61RcliCrYH/RwN    f8XTLx/Ga04w2qEIFlLOiuH6x/KA22muOLYaSIefXv38xj0Hj41iE5ZIseaLuJogn7iqJ6Fq0wQH    i6ueF9BasSWnOHhn6CJamYz3FC9r2m3vwPMkgagPp1FdYyDxodK+MZlwu6TxqP6QQ7BY/Wh5DZK8    C8zpDOZGQgWOrghF58TlZSmJYmukv1NqsY8PCFuoj7vfoUzVKQkyKcEiohwBcTb50vGPl06bMQ==     hadoop@HadoopSlave2

把HadoopMaster的authorized_keys拷贝到HadoopSlave1和HadoopSlave2

scp ~/.ssh/authorized_keys hadoop@HadoopSlave1:~/.ssh/
scp ~/.ssh/authorized_keys hadoop@HadoopSlave2:~/.ssh/

重启SSH服务

sudo service sshd restart

测试连接

ssh HadoopSlave1

常见免密码登录失败分析

配置问题

检查配置文件/etc/ssh/sshd_config是否开启了AuthorizedKeysFile选项
检查AuthorizedKeysFile选项指定的文件是否存在并内容正常

目录权限问题

~权限设置为700
~/.ssh权限设置为700
~/.ssh/authorized_keys的权限设置为600

sudo chmod 700 ~
sudo chmod 700 ~/.ssh
sudo chmod 600 ~/.ssh/authorized_keys

引用地址：https://www.cnblogs.com/keitsi/p/5653520.html