SSH使用秘钥安全登陆（ssh密钥登陆）

比如：A(192.168.0.115)要无密码登陆B(192.168.0.134) 1.在A上生成秘钥

ssh-keygen -t rsa

2.把秘钥拷贝到B

scp /root/.ssh/id_rsa.pub root@B:/root/.ssh

3.在B上操作

cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys

4.测试，在A上连接B

ssh 192.168.0.134
Last failed login: Wed May 16 11:45:27 CST 2018 from 192.168.0.115 on ssh:notty
There was 1 failed login attempt since the last successful login.
Last login: Tue May 15 10:16:31 2018 from 192.168.0.156
[root@localhost ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
 inet 127.0.0.1/8 scope host lo
 valid_lft forever preferred_lft forever
 inet6 ::1/128 scope host
 valid_lft forever preferred_lft forever
2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
 link/ether 08:00:27:7c:b0:ee brd ff:ff:ff:ff:ff:ff
 inet 192.168.0.134/24 brd 192.168.0.255 scope global dynamic enp0s3
 valid_lft 1639sec preferred_lft 1639sec
 inet6 fe80::5afa:9ce7:f6a7:b765/64 scope link
 valid_lft forever preferred_lft forever
3: bond0: <BROADCAST,MULTICAST,MASTER> mtu 1500 qdisc noop state DOWN qlen 1000
 link/ether 2a:3d:e1:11:ed:5c brd ff:ff:ff:ff:ff:ff

5.备注 密钥的权限(600 或者644)，否则会连接不上。