3台linux服务器互信

[root@mydb1 ~]# hostname

mydb1

1、改主机名，由mydb1改为mydb100

vi /etc/sysconfig/network

将HOSTNAME后面的值改为想要设置的主机名

HOSTNAME=mydb100

2、每个节点加入最后三行

[root@mydb1 ~]# vi /etc/hosts

127.0.0.1localhost localhost.localdomain localhost4 localhost4.localdomain4

::1 localhost localhost.localdomain localhost6 localhost6.localdomain6

192.168.28.100 mydb100

192.168.28.101 mydb101

192.168.28.102 mydb102

3、生成公钥和私钥，每个节点都执行

在/root/.ssh下执行生成公钥和私钥命令，即公钥私钥存放在该目录下才生效

cd /root/.ssh

ssh-keygen是生成密钥命令 -t 指定密钥类型，默认是 rsa ，可以省略，-f 指定密钥文件存储文件名

[root@mydb102 .ssh]# ssh-keygen -t dsa -P '' -f id_dsa

Generating public/private dsa key pair.

Your identification has been saved in id_dsa.

Your public key has been saved in id_dsa.pub.

The key fingerprint is:

36:77:57:c2:bf:2c:c1:5a:15:84:c4:d7:2f:91:86:00 root@mydb100

The key's randomart image is:

+--[ DSA 1024]----+

|E...ooo+.|

|.++.o|

| .+oo|

|. o+.|

|S . .+...|

|. o .o.o .|

|. . o |

| . |

| |

+-----------------+

[root@mydb100 .ssh]# ll

total 16

-rw-r--r-- 1 root root 1806 Aug 10 17:46 authorized_keys

-rw------- 1 root root 672 Aug 10 17:13 id_dsa

-rw-r--r-- 1 root root 602 Aug 10 17:13 id_dsa.pub

-rw-r--r-- 1 root root 1570 Aug 10 17:48 known_hosts

4、 将公钥添加到认证文件中

[root@mydb100 .ssh]# cat id_dsa.pub>>authorized_keys

# 只要在一个节点执行即可。这里在 192.168.28.100上执行

scp 192.168.28.101:/root/.ssh/id_dsa.pub ./id_dsa.pub.101

scp 192.168.28.102:/root/.ssh/id_dsa.pub ./id_dsa.pub.102

cat id_dsa.pub.101>>/root/.ssh/authorized_keys

cat id_dsa.pub.102>>/root/.ssh/authorized_keys

5、 分发整合后的文件到其它节点

scp authorized_keys 192.168.28.101:/root/.ssh

scp authorized_keys 192.168.28.102:/root/.ssh

6、测试互信验证

测试时，第一次，需要输入密码，之后就不需要输入密码了。

[root@mydb102 .ssh]# ssh mydb100

Last login: Fri Aug 10 17:48:26 2018 from mydb101

[root@mydb100 ~]# ssh mydb101

Last login: Fri Aug 10 17:48:51 2018 from mydb102

[root@mydb101 ~]# ssh mydb102

Last login: Fri Aug 10 17:48:49 2018 from mydb101

[root@mydb102 ~]# ssh 192.168.28.100

Last login: Fri Aug 10 17:48:57 2018 from mydb102

[root@mydb100 ~]# ssh 192.168.28.102

Last login: Fri Aug 10 17:49:10 2018 from mydb101