Linux下配置ssh无密码登陆

124q31

mkdir ~/.ssh
chmod 700 ~/.ssh
ssh-keygen -t rsa
ssh-keygen -t dsa
然后，在节点 dbtest1 执行以下命令
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
ssh dbtest2 cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
ssh dbtest2 cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
scp ~/.ssh/authorized_keys dbtest2:~/.ssh/authorized_keys


节点1：
node1:~ #cd /root
node1:~ # mkdir .ssh
node1:~ # chmod 700 .ssh
node1:~ # ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
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.
The key fingerprint is:
b0:1d:73:0a:99:2a:ee:ce:cd:5f:de:e5:db:c9:ab:6e [MD5] root@node1
The key's randomart image is:
+--[ RSA 2048]----+
|                 |
|       o         |
|      = o .      |
|     . = =       |
|  . . . S        |
| . .             |
|  .     .   .    |
| o o   o . oEo . |
| .+ o.. . .o=o=. |
+--[MD5]----------+
node1:~ # ssh-keygen -t dsa
Generating public/private dsa key pair.
Enter file in which to save the key (/root/.ssh/id_dsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_dsa.
Your public key has been saved in /root/.ssh/id_dsa.pub.
The key fingerprint is:
9c:93:19:6b:df:bd:f3:01:b6:82:be:32:0c:ee:b0:68 [MD5] root@node1
The key's randomart image is:
+--[ DSA 1024]----+
|                 |
|                 |
|        .        |
|       . *       |
|        S    o   |
|     . . o....o  |
|   .. o  ....... |
| E. o. +.   . ...|
|.. ...  oo.   .o.|
+--[MD5]----------+
node1:~ #

节点2
node2:~ # cd /root
node2:~ # mkdir .ssh
node2:~ # chmod 700 .ssh/                              
node2:~ # ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
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.
The key fingerprint is:
f2:ca:0c:73:98:04:55:69:48:1a:9a:a8:8e:0c:96:0c [MD5] root@node2
The key's randomart image is:
+--[ RSA 2048]----+
|  ..oo..         |
|.o +. o          |
|E o  .           |
|+ ..             |
|o+  . . S        |
|*  . o o         |
|.o  = . .        |
|     * .         |
|      +          |
+--[MD5]----------+
node2:~ # ssh-keygen -t dsa
Generating public/private dsa key pair.
Enter file in which to save the key (/root/.ssh/id_dsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_dsa.
Your public key has been saved in /root/.ssh/id_dsa.pub.
The key fingerprint is:
6a:c4:e1:cc:bb:c7:32:51:5c:96:49:46:24:df:86:ad [MD5] root@node2
The key's randomart image is:
+--[ DSA 1024]----+
|        .+=o     |
|         +=+     |
|      .. oo +    |
|     = .o  o     |
|      *.S E      |
|     ..o         |
|      +o         |
|     .o.o        |
|      .+         |
+--[MD5]----------+
node2:~ #

同步authorized_key

node1:~/.ssh # cat id_rsa.pub >>authorized_keys
node1:~/.ssh # cat id_dsa.pub >>authorized_keys
node1:~/.ssh # ssh node2 cat /root/.ssh/id_rsa.pub >> authorized_keys
The authenticity of host 'node2 (10.0.0.31)' can't be established.
ECDSA key fingerprint is b4:30:1b:97:e9:75:1e:e2:2c:85:91:2a:76:85:77:ce [MD5].
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'node2,10.0.0.31' (ECDSA) to the list of known hosts.
Password:
node1:~/.ssh # ssh node2 cat /root/.ssh/id_dsa.pub >> authorized_keys
Password:
node1:~/.ssh # scp authorized_keys node2:/root/.ssh/
Password:
authorized_keys                               100% 1984     1.9KB/s   00:00   
node1:~/.ssh #
测试
node1:~/.ssh # ssh node2 date
Sat May  9 05:40:58 CST 2015
node1:~/.ssh #
node2:~ # ssh node1 date
Sat May  9 05:41:03 CST 2015
node2:~ #